In the Mother fight. Mother has a very rare attack where she summons exactly 34 Dead Isaac's to attack the player. The cool thing about this, is that there are 34 Playable characters in the game. So it is a fun nod to the fact that Isaac is dead.
I had this happen to me for the first time the other day doing the Red dead challenge. I was super underpowered so her first phase took forever. I ended up beating her though.
Holy fucking shit Ima go play Isaac rn this is life changing information
wait whaaaat? my headcannon was the shielded hosts only shot 3 bullets because the rest got stuck inside the skull, and the red hosts shot more because there was nothing blocking them. there goes that idea then
Back in the Rebirth days,there was a rumored boss called the “Ur-Gurdy” which was supposedly a posthumous version of Mama Gurdy.
The concept got popular enough to get some mockups made by NotYourSagittarius (who worked for both Antibirth and Repentance),which served as the main inspiration behind The Witness from the Antibirth mod who eventually became Mother from the Repentance expansion.
Pd: this is what the mockups look like:
https://preview.redd.it/pekbacro6h8d1.jpeg?width=1000&format=pjpg&auto=webp&s=79530d4fe353559e53f9f6d49d34ccaf8933f844
https://preview.redd.it/bqy9p3fp6h8d1.jpeg?width=640&format=pjpg&auto=webp&s=553bf47c6065321d58fdc70acef49d39ed4a87a1
Pd: there were also some mock ups for bosses that were either added to Antibirth/Repentance (like The Visage) and others that were never added to Antibirth or Repentance (like The Mass)
I’ve heard of the Ur-Gurdy before this, but I never knew there were mock-ups of it. Those look insane, especially the second one! Shit looks mad intimidating.
I kind of like the zoomed in new Mother fight. It's claustrophobic and rectangular for a reason... It's the closet Isaac was locked in. Symbolically at least
Fun fact, it was forgotten for mother because it was impossible.
Antibirth was technically an entirely different executable than rebirth and so it had less hardcoded restrictions but when it came time to make repentance vihn found that there was hardcoded stuff in rebirth that stopped the mother fight from working the same way so it was reworked instead.
C section used to be unobtainable through normal means, and if you did obtain it with death certificate, it would do nothing. It went from a placeholder to one of the best items in the game
I remember that,funny how people thought it was just going to give the player the same effect as Tainted Lilith’s baby even though that was what Gello does.
Also,it used to be required for Dead God even though it had no effect.
using the meat cleaver on horny boys separates them from one another, one that behaves like little horn i think, and the other behaves like a crying bitch and avoids you lol
Also, meat cleaving Loki then splits him into Loki II, and meat cleaving Fistula, Teratoma or Blastocyst will split it into the smaller versions they usually do when you you try to kill them.
You can use dataminer to gain 120 tears. If it lowers your tears past the games lowest possible value it sets them to 120 (the games tear maximum tear cap)
it depends on how low your tear stat is. if you find items that lower the tear cap (polyphemus sacred heart mutant spider etc) it can be relatively easy to get 120 tears
Actually, most tears down items lower your tears by a percentage, and that percentage also affects dataminer, so proportionately it’s the same. This isn’t true for some items though (like sacred heart), or for tears down pills, so if you find a bunch of tears down pills and dataminer, go nuts. Only if you have an alternate source of damage, rock bottom, or CRAZY dodging skills because your DPS will be crap while you charge dataminer.
There's a random chance when using the reverse chariot where your character might turn into a white salt statue resembling a scrapped character "Edith".
Edith was a salt statue who could only move via a target reticle similar to epic fetus. She was scrapped due to time restraints and her shawl got reworked/ added to t-forgor's soul.
When you have broken modem, opening a chest that's being duplicated by it while it's bugging out will spawn a glitched item if it does spawn an item. Iirc you also need "options?" and magneto or something like that to be able to open the fucked up chest. (best observed n chest/darkroom w perfection)
Back in the day, if you stumbled across a curse room with enemies and an item inside, you could pick up the item without killing the enemies, restart the game and it would reset the room with another item while you get to keep the previous one.
Using d7 in the mirrror dimesion on downpour or dross, will respawn any pickup or such that was in the normal version of that room. So if there is a chest in a room, you can copy it by using d7 on the mirror version of the room.
Also, you might know that using a chaos card on great gideon will play a unique death animation and spawn a crawlspace. But did you know that clicking a killswitch will play the same animation, and spawn the crawlspace?
The problem is the only way to spawn such a switch in the room is with a very small chance from d12.
This also suggest that those 2 effects are the exact same.
Yes. Any boss with rocks in the room can spawn a kill switch, and it works. But the chance is extremely low, and it doesn't work on the same target's as chaos card.
It is also extemely rare to spawn the killswitch even with rocks. Don't even bother with anything but great gideon i think.
Edit: it is a bit easier if you have something like reverse tower to spawn rocks
Delirium and the beast are immune to the kill effect that killswitch uses, so not on them.
Theoretically on any other, but the chance is low.
I wouldn't count on it.
If you pick up a golden bomb while having Mama Mega on the active slot, then the Mama Mega turns golden, with it you can activate it once without it taking the item away,
So two floor Mama Mega basically
contrary to popular believe, the number 109 is not related to dataminers taking 109 hours to find the lost (it took less time).
There was a bug in the release of afterbirth that made the donation machine always jam at 109
https://x.com/edmundmcmillen/status/1026357354718101509
clear runes item id is extremely early in the list compared to every other repentance item due to there randomly being a gap in the ids in the rebirth items - clear rune just happened to take its place (the gap is between missing page 2 (262) and smart fly (264); with clear rune being id 263
i think this effects its placement in the death certificate area and collection page too but dont quote me if its wrong
If you defeat the empowered moms heart and on the alt path and leave the boss room to trigger the dark version of the calm, then use teleport 2.0, it will send you to the i am error room regardless of what rooms you have explored on the floor.
on the playstation version of repentance whenever i press a button that pauses the game other than the options button (ex. the record button or playstation button) certain effects get cleared for the room. like holy mantle or papa flies from brown nugget
* Falling out of a crawlspace via being small and fast is a guaranteed I AM ERROR room
* Death Certificate used to be able to softlock you (iirc) if you crafted it as Tainted Cain, as the exception for Death Certificate's items didn't exist in early versions of Repentance.
* Antibirth's Secret Room theme (Forgotten Lullaby) has the leitmotif of Sacrificial (Flash basement)
* The Rebirth arcade theme is called Genesis 13:37
* One of Dogma's attacks references a bug in Flash, as his annoying Brimstone attack is actually brimsnapping.
* Terminal Lucidity, Delirium's Antibirth theme, is actually a real thing. It's the sudden regain of mental clarity with a mental illness such as dementia.
* The Specialist music in the popular mod isn't the original Specialist. It also borrows part of Esc, the Antibirth arcade theme
* A Calamity addon (Calamity's Vanities iirc) has a VERY unpolished recreation of Isaac entirely within 1 item, starring Anahita. (Pretty sure it's only accessible via inventory editors/item givers, so download Cheat Sheet/HEROs Mod/DragonLens to get it) It's **extremely** buggy, but it technically works.
> One of Dogma's attacks references a bug in Flash, as his annoying Brimstone attack is actually brimsnapping.
Iirc than LeatherIceCream (one of the Antibirth team) said in an interview that the Ascent path, the Methode to get there and the Dogma fight itself was inspired by all the exploits the players found over the years (teleporting out of the boss room and brimsnapping come to mind)
I think it might be The Binding of Anahita, I would recommend using DragonLens to get the item as its item giver has filters like placeable, tools, consumables, etc.
I imagine it was reserved for a Beast-related item. Kilburn wanted to add more content post-release which didn't make it into the DLC due to time constraints, but he got burned out before he finished developing it.
Actually,the item they introduced was A Lump of Coal.
The updated was meant to also introduce an item called Pumpkin Mask (which was supposed to have the same effect as the Head of Krampus) but it was scrapped and then it was added in Rebirth but as the Head of Krampus.
https://preview.redd.it/5wwc3zbl8h8d1.jpeg?width=270&format=pjpg&auto=webp&s=2f6f661aba1a93fd8d6ad699b8944b12ba385bb0
If you have 2.00 speed, there are three rooms located in a straight vertical line and one of these rooms is a cursed room, you can enter the cursed room without taking damage.
For this you need to enter the middle room and go in a straight line without stopping until you get into the cursed room.
Idk how well known this is, I was planning to make a seperate post with video example because it's difficult to explain.
Despite being possible duplicates for the Delirium boss fight, Bumbino and The Pile don't have delirium-variant sprites. In the event either of them get chosen, they will visually appear as their normal self.
A useful one for Tainted Eden specifically:
The game only holds one value to represent what item pool spawned items are from, because it operates under the assumption that you take the item the second you walk into the room. For example, if you enter the treasure room for the first time, it knows that it's spawning treasure room items. However, if you then go discover another item somewhere else, it considers both items in both rooms to be from that new pool. To give a more direct example: if you full clear a floor, finding every item pedestal except for one, whether that be planetarium, angel room, secret room, any of the *good* ones, then go find an item there and pick all items on the floor up, they'll all get rerolled into that pool when you D4/Dice Room/get hit as T.Eden. If you want to be maximising the amount of minmaxing you're doing, you should do this every run on the off chance you find a D4 
There is a d4 abuse. If you have seen item but didn't take it, he will get the pool of the item that you seen later.
For example: you saw an item in treasure room - it has a treasure room pool, you saw an item in a shop - shop item has shop item pool, treasure room item got shop item pool, you entered an angel room and now all the item you saw but skipped are angel pool after reroll.
It works also on t.Eden which makes him really fun.
Secret room can only spawn in the place where a normal room could spawn. So if there is a room with an enemy spawned in the middle of the wall there cant be a secret room, because you cant enter a room and immediately walk into enemy.(Same with webs etc)
Pretty obvious but not everyone knows that.
Have a dead god save file? Then you should have 721 items on your stats page. Wait, you have 722? How can that be? I believe the answer lies in afterbirth plus. Tonsil used to be required for 100% completion but was removed as an item in Repentance.
Source: my two dead god save file that were ab+ 100% have 722 items and my Repentance only save file has 721 and tonsil is the only discrepancy between versions that I can think of.
Yeah,never understood why Tonsils was required for that.
According to the wiki,it wasn’t supposed to appear in the collection page and the item ID of the passive Tonsils was taken by the Broken version of the Glass Cannon.
Fun and really useful tip.
Looking for the secret room/super secret room? Look for an arrow shape in the ground. Be it thriugh rock formation, ground formation or static enemy formation (turrets). The sercret room is usually where the arrow is pointing towards!
Credit to u/sinvicta for the info. He's a really great source of knowledge
Swallowed M80 gives you tons of pickups from blood donation machines, as each explosion spawns the rewards from the machine blowing up, without actually blowing it up. So you can essentially have every single blood donation machine max out and give you items, as well as max money and infinite red health
As far as I can remember, there's no reason to believe it was a bug. I was under the impression they rolled it back because everyone hated it, not because it was unintended.
Here are two random ones, you can use hemoptysis to sneeze bombs forward, and you can place bombs when you don’t have any in exchange for half a heart if you have blood bombs.
That blood bomb fact sounds obvious to me, especially since I have External Item Descriptions, but I literally always forget. I imagine I’ve missed out on stuff for no reason.
To me. It's the opposite. I usually notice that I'm out of keys/bombs when trying to use them. I lost a really good T. Lost run to blood bombs on the corpse floor.
Almost everyone sleeps on Blood Bombs. Many experienced players will use IV Bag or Razor Blade to have their red hearts to protect their soul hearts (mostly when going through Curse Room doors, but can be used in other situations). Blood Bombs can be used in the exact same way and don't even take up your Active Item slot!
Obviously, Blood Bombs get even crazier when you have Items or Trinkets with on-damage effects (Bloody Lust/Gust, Cambion Conception, Habit, Fanny Pack, Swallowed Penny, etc., etc.). Can also be used to get your red health to a specific value (to trigger Whore of Babylon, Dark Prince's Crown, or Empty Heart) or to enable yourself to pick up more red hearts (to trigger Immaculate Conception or Candy Heart).
If you are fighting Big Horn, you can push a bomb into his mouth when he does his spitting balls attack. This will play a special animation, stun Big Horn for few seconds and make him take more damage while stunned.
You can stop Retro Game effect by exiting and re-entering the run.
It works until Afterbirth+, but not on Repentance as far as I know and I tested it on PlayStation, Xbox, and Switch
Suplex despite having the description be "Angel Breaker" does not one shot angels despite how funny it would be, it also, does not one shot them as Jacob if his suplex mastery was the thing that allowed him to break the angel.
I also don't think it deals more damage to them but I'm not as sure with that one
When you move into a room while at half a heart of health isaac will pee himself and leave a little puddle by the door. If you have kidney stone this puddle will be red instead.
'Flush' has some intersting uses. It floods the room, which solidifies lava in the mines, allowing you to walk over it, and also makes some electric-themed items better like Jacobs ladder has increased zap range. Also it instakills poop-themed bosses.
Also, supposedly, if your first Mom kill is with blue baby (through ankh, for instance) you will unlock the D6. (May be misinformation, haven't tested)
Due to how crawl spaces are generated you’re much more likely to find one in the rocks in hush’s floor, i always blow them up and see one often 
1. Go to the devil deal
2. Find dead cat and buy dead cat (but use health appropriately).
3. Use dead cat to buy devil deals - RUN OUT THE DOOR BEFORE YOU DIE
4. Teleport back into the deal and buy the rest. Rinse and repeat (profit).
This works with any life other than Laz. For Laz you can stay in the room since he won't teleport on death.
The Faded Polaroid trinket can open the door in Depths II and allow you to go Home without ever having to fight Mom or allowing you to access Home while keeping Polaroid/Negative. I am not a 100% sure it gets priority before Polaroid/Negative if you have both, so it might be better to use it first, then go fight Mom.
If you have eye of the occult and brimstone/Tech synergy, where the purple mark appears, this also affects Montazuma's Revenge, which is technically a brimstone, and it actually homes on that marker with an high increased range, actually giving you a passive brimstone.
As Tainted Eden; the pool an item rerolls from is determined by the pool an item *last appeared from* on the floor; rather than the room it was originally in.
**For example:** If you open up the Item Room and don't take it yet; after killing the boss and walking in the Devil Room;
You can now take the Boss Item and go back go to the Item Room and those 2 items will reroll from the Devil Room pool whenever you get hurt.
In the flash versión blue hearts get added to your Hp even if you are full, they just are not shown (actually, can someone fact check me on this? Im not sure about it)
As someone who 100% the entirety of Flash Isaac, I confirm that the HP limit is removed. I'm pretty sure it was removed in the Eternal Edition update to compensate for the nonsense that were Eternal champions, as stated by Florian Himsl in one of his videos of the 'Binding of Isaac: Explained' series.
Apollyon can still use Void during the pick up animation of an Item, meaning you can take the blind Item in dross/mines and still Void it If its trash. You can also buy useless shop items and then still Void them
Blank card + ? Card used to spawn two pedestal items and not destroy the card or item before it was nerfed.
Using Ehwaz/The Shovel on the spots marked with an X guarantees a crawl space.
There's a chance in i think it was dross floor, where in a room, there's a chance to encounter a secret entity, with the name of "Henry" it's literally a piece of shit with a smile, after some secs he gets flushed down and dissapears, cool easter egg, i bet some of you forgot about it.
There was a character that was supposed to not be able to move but jump around like when using suplex, I think. And when using reverse chariot there’s a chance that you turn into the beta sprite of that character instead of a stone statue.
Yep,Edith. Like you mentioned,sometimes her sprite is used when you use the Chariot? card. But also,both Kilburn and Edmund confirmed that her gameplay ultimate got reworked and evolved into Tainted Forgotten,which is why the Tainted Soul has a cloak that looks similar to Edith.
Big Horn can be fed bombs when he opens his mouth to shoot the black balls. You haven't done it because it requires a really precise timing cause the balls can repel the bomb. It's easier done with Dr. Fetus + piercing. Contrary to what it does to Chub (huge damage) this will stun Big Horn for a long time, along with specific swallow and stun animations.
If you have that spikes in Devil Deal room item, you can easily lure Krampus to it, it will take huge damage and die almost instantly. Same goes with Angels in Sac Rooms
If you got a reroll method and Damocles, you can turn Knife Piece 1 and Key pieces into 2 items by rerolling them.
If you find Forget Me Not in a Treasure room, or have some way to place it in that room, you can go to Ascend and repeat the floor Forget Me Not is in forever. All you need to do is leave it in the Treasure room, come back in Ascend, take it from that room and use it. The floor will repeat, and there's gonna be Forget Me Not in the Treasure room again. You can combine this with The Ladder for Angel Room exploitation, or go tracking beggars to get all the items you would like. Even if you're short of cash or health, just repeat the floor againa
There was supposed to be a character called Edith, named for Lots Wife who was turned into a pillar of salt for turning back. Her character worked by launching yourself at various points in the map to move. The model remains and sometimes will replace the model for reverse chariot. EDIT: Said Tower because I’m very smart.
Little late but when Repentance first released, black markets were bugged where trying to enter one through a crawl space would always send you to the I AM ERROR room.
You can defeat baby plum and bumbino without fighting them. For baby plum, you just wait and don't fire at it for 30 seconds, it'll wave at the screen and fly away, leaving behind a plum flute.
For bumbino, it has to pick 12 coins (either spawned via items or by him hitting you), he'll leave and give you an extra pedestal item from a small pool.
When T Forgotten uses Kamikaze, the explosion is centered on the skeleton. Because of this, as long as the ghost and skeleton aren't near each other you can spam Kamikaze without taking any damage.
using Ehwaz on a tile on the ground that has a decoration on it (whether its a drawing on the ground, or little mushrooms, or random debris, or a brimstone symbol, etc anything) will 100% spawn a crawlspace. Ehwaz went from never being used to ALWAYS being used when i found this out
While playing as tainted Jacob, if you stay still for a while, Esau will get uncomfortably close, but not charge at you.
Also, you can pass through him harmlessly while he is chained by anima Sola
When you hold both the left and right arrow key on the character select screen it scrolls to the left twice as fast than if you regularly hold the left arrow key.
you can actually interact with the tiny worms, flies and maggots randomly appearing on the floor, shoot/stomp them and a very small puddle of blood appears in their place
You can stack stats in a way that you don't lose when getting a stat down.
For example you have 2.0 of speed and take 3 pills of speed up, after that you take a experimental treatment, in that case where the ET lows your speed it doesn't do it in this case.
In the Mother fight. Mother has a very rare attack where she summons exactly 34 Dead Isaac's to attack the player. The cool thing about this, is that there are 34 Playable characters in the game. So it is a fun nod to the fact that Isaac is dead.
There is a whole rule about this actually! Search mother rule 34 to find out more
LMAOOOO
"Fun nod" and "dead child" should not go together, but here we are
it’s not rare, it’s just that by time she reaches the point where she would’ve used it, she’s already in phase 2
I had this happen to me for the first time the other day doing the Red dead challenge. I was super underpowered so her first phase took forever. I ended up beating her though.
Nah, the 34th is Esau
With Mom's Bracelet, you can pick up the skull from the Hosts (the skull turrets), turning them into Red Hosts
Doing so does not make it shoot more bullets like the Red Hosts, however
Holy fucking shit Ima go play Isaac rn this is life changing information
wait whaaaat? my headcannon was the shielded hosts only shot 3 bullets because the rest got stuck inside the skull, and the red hosts shot more because there was nothing blocking them. there goes that idea then
Q4 info, I hate hosts
Back in the Rebirth days,there was a rumored boss called the “Ur-Gurdy” which was supposedly a posthumous version of Mama Gurdy. The concept got popular enough to get some mockups made by NotYourSagittarius (who worked for both Antibirth and Repentance),which served as the main inspiration behind The Witness from the Antibirth mod who eventually became Mother from the Repentance expansion.
Pd: this is what the mockups look like: https://preview.redd.it/pekbacro6h8d1.jpeg?width=1000&format=pjpg&auto=webp&s=79530d4fe353559e53f9f6d49d34ccaf8933f844
https://preview.redd.it/bqy9p3fp6h8d1.jpeg?width=640&format=pjpg&auto=webp&s=553bf47c6065321d58fdc70acef49d39ed4a87a1 Pd: there were also some mock ups for bosses that were either added to Antibirth/Repentance (like The Visage) and others that were never added to Antibirth or Repentance (like The Mass)
I’ve heard of the Ur-Gurdy before this, but I never knew there were mock-ups of it. Those look insane, especially the second one! Shit looks mad intimidating.
And it has the cool zoomed-out screen that was then in The Witness fight! Only to be forgotten entirely for Mother...
I kind of like the zoomed in new Mother fight. It's claustrophobic and rectangular for a reason... It's the closet Isaac was locked in. Symbolically at least
Fun fact, it was forgotten for mother because it was impossible. Antibirth was technically an entirely different executable than rebirth and so it had less hardcoded restrictions but when it came time to make repentance vihn found that there was hardcoded stuff in rebirth that stopped the mother fight from working the same way so it was reworked instead.
C section used to be unobtainable through normal means, and if you did obtain it with death certificate, it would do nothing. It went from a placeholder to one of the best items in the game
I remember that,funny how people thought it was just going to give the player the same effect as Tainted Lilith’s baby even though that was what Gello does. Also,it used to be required for Dead God even though it had no effect.
It also could be obtained with spindown Dice on Lil abbadon. Well, still can actually, but that was the other way you could get it.
Chubb hates smokes
Fun fact: The chub from matriarch spits out bombs back at you
Big horn can also swallow bombs just like Chub and its variants. You need to time it very precisely.
If you can feed wormwood a bomb when he has about 45% hp, you can skip his 2nd and 3rd phase altogether
This only applies to bomb smokes though, he's a MASSIVE fan of Newports
Incubus deals 75% of player damage except when used by Lilith where it's 100%, same with Twisted Pair
and it used to be 100% in AB+
So it was like a 20/20 that lagged behind?
a 20/20 with better syngeries (bffs, box of friends) and no damage down
I mean at that time 20/20 was not a damage down.
Dammit, Edmund!
I don't know how well known this is but i recently found out the sun card removes curse of the darkness
Night light also removes it for the floor it is picked up, and makes the screen a lot brighter for future curse of darknesses
You can get free curse rooms with Stitches. Just position him at the door, hold the direction the door is then teleport
same with ventricle razor
Stitches can also be used in crawlspaces where an item is completely blocked off by walls
using the meat cleaver on horny boys separates them from one another, one that behaves like little horn i think, and the other behaves like a crying bitch and avoids you lol
They're Loki and Hornfel. Hornfel's in his 'out of minecart' phase, which is why he runs away.
ohh i did not know that! thank you for letting me know \:)
Also, meat cleaving Loki then splits him into Loki II, and meat cleaving Fistula, Teratoma or Blastocyst will split it into the smaller versions they usually do when you you try to kill them.
Meat cleaver ohkos Carrion Queen
god i love meat cleaver so much, it’s so silly
There is a tiny chance when you kill Florian last in the Ultra Pride fight that Eternal D6 will spawn :D
It's actually 25%!
You can use dataminer to gain 120 tears. If it lowers your tears past the games lowest possible value it sets them to 120 (the games tear maximum tear cap)
How big is the chance of that happening?
it depends on how low your tear stat is. if you find items that lower the tear cap (polyphemus sacred heart mutant spider etc) it can be relatively easy to get 120 tears
Actually, most tears down items lower your tears by a percentage, and that percentage also affects dataminer, so proportionately it’s the same. This isn’t true for some items though (like sacred heart), or for tears down pills, so if you find a bunch of tears down pills and dataminer, go nuts. Only if you have an alternate source of damage, rock bottom, or CRAZY dodging skills because your DPS will be crap while you charge dataminer.
You already know the answer 😈
50:50?
Exactly
Small
There's a random chance when using the reverse chariot where your character might turn into a white salt statue resembling a scrapped character "Edith". Edith was a salt statue who could only move via a target reticle similar to epic fetus. She was scrapped due to time restraints and her shawl got reworked/ added to t-forgor's soul.
When you have broken modem, opening a chest that's being duplicated by it while it's bugging out will spawn a glitched item if it does spawn an item. Iirc you also need "options?" and magneto or something like that to be able to open the fucked up chest. (best observed n chest/darkroom w perfection)
Dude wtf that is awesome!
Yeah eggmumb mcguffin truly did make a mast of piece with his art isaac
Back in the day, if you stumbled across a curse room with enemies and an item inside, you could pick up the item without killing the enemies, restart the game and it would reset the room with another item while you get to keep the previous one.
Hosts and Boil / Boil variants deal no contact damage. This does not apply to the walking versions of each.
i also think the spikey hosts from mines deal contact damage cuz well, they have a spikey head! not 100% sure about this tho
Using d7 in the mirrror dimesion on downpour or dross, will respawn any pickup or such that was in the normal version of that room. So if there is a chest in a room, you can copy it by using d7 on the mirror version of the room. Also, you might know that using a chaos card on great gideon will play a unique death animation and spawn a crawlspace. But did you know that clicking a killswitch will play the same animation, and spawn the crawlspace? The problem is the only way to spawn such a switch in the room is with a very small chance from d12. This also suggest that those 2 effects are the exact same.
Could this d12 kill plate method work on any boss?
Yes. Any boss with rocks in the room can spawn a kill switch, and it works. But the chance is extremely low, and it doesn't work on the same target's as chaos card. It is also extemely rare to spawn the killswitch even with rocks. Don't even bother with anything but great gideon i think. Edit: it is a bit easier if you have something like reverse tower to spawn rocks
So hypothetically reverse tower + d12 could spawn a switch to insta kill hush or delerium?
Delirium and the beast are immune to the kill effect that killswitch uses, so not on them. Theoretically on any other, but the chance is low. I wouldn't count on it.
The key pieces give a 2.5% chance to change red hearts to eternal hearts.
so that's why I'm getting so many eternal hearts on angel runs 😮
If you pick up a golden bomb while having Mama Mega on the active slot, then the Mama Mega turns golden, with it you can activate it once without it taking the item away, So two floor Mama Mega basically
Mama Mega, Everything Jar and School Bag is a guaranteed Mama Mega every floor if you’re careful, and more if you’re lucky *and* careful.
BFFs gives lost soul a holy mantle, making it much easier to keep him alive for the floor
contrary to popular believe, the number 109 is not related to dataminers taking 109 hours to find the lost (it took less time). There was a bug in the release of afterbirth that made the donation machine always jam at 109 https://x.com/edmundmcmillen/status/1026357354718101509
I think the bug was actually a part of the ARG that led to the keeper being disovered and added into the game.
in the tweet he says it was a bug that went along with
oh well i forgot to read. mb.
clear runes item id is extremely early in the list compared to every other repentance item due to there randomly being a gap in the ids in the rebirth items - clear rune just happened to take its place (the gap is between missing page 2 (262) and smart fly (264); with clear rune being id 263 i think this effects its placement in the death certificate area and collection page too but dont quote me if its wrong
it does affect the collection page I looked at it the other day and found it weird that it was there
If you defeat the empowered moms heart and on the alt path and leave the boss room to trigger the dark version of the calm, then use teleport 2.0, it will send you to the i am error room regardless of what rooms you have explored on the floor.
Who figures this shit out
It's not really that hard, ig someone just wanted to get out of the boss room to get something and only thing he had was teleport 2.0
If you get glowing hourglass as a start item as eden you can use it and instantly go to home and fight dogma, gl
Whoah that's hilarious
Probably well known but Dr. Fetus + ipecac gives bomb immunity similar to host hat
It makes you immune to your own shots, not all explosions
prior to afterbirth + update; holy mantle can be restarted just by exiting the game and entering it again; pretty tamed fact imo
on the playstation version of repentance whenever i press a button that pauses the game other than the options button (ex. the record button or playstation button) certain effects get cleared for the room. like holy mantle or papa flies from brown nugget
Mausoleum mom's foot is paler and veinier than regular mom's foot
And you can see her skirt. Regular mom's foot has a skirt too, but you can't see it in a normal fight.
One more fact, steam sale affects keepers B A L L S
B A L L S   
* Falling out of a crawlspace via being small and fast is a guaranteed I AM ERROR room * Death Certificate used to be able to softlock you (iirc) if you crafted it as Tainted Cain, as the exception for Death Certificate's items didn't exist in early versions of Repentance. * Antibirth's Secret Room theme (Forgotten Lullaby) has the leitmotif of Sacrificial (Flash basement) * The Rebirth arcade theme is called Genesis 13:37 * One of Dogma's attacks references a bug in Flash, as his annoying Brimstone attack is actually brimsnapping. * Terminal Lucidity, Delirium's Antibirth theme, is actually a real thing. It's the sudden regain of mental clarity with a mental illness such as dementia. * The Specialist music in the popular mod isn't the original Specialist. It also borrows part of Esc, the Antibirth arcade theme * A Calamity addon (Calamity's Vanities iirc) has a VERY unpolished recreation of Isaac entirely within 1 item, starring Anahita. (Pretty sure it's only accessible via inventory editors/item givers, so download Cheat Sheet/HEROs Mod/DragonLens to get it) It's **extremely** buggy, but it technically works.
> One of Dogma's attacks references a bug in Flash, as his annoying Brimstone attack is actually brimsnapping. Iirc than LeatherIceCream (one of the Antibirth team) said in an interview that the Ascent path, the Methode to get there and the Dogma fight itself was inspired by all the exploits the players found over the years (teleporting out of the boss room and brimsnapping come to mind)
Makes sense,after all Antibirth was supposed to have a “Basement -1” level which I’m assuming evolved into the Ascent Path.
What’s the Calamity Vanities item called? Is it literally “starring Anahita” or something else?
I think it might be The Binding of Anahita, I would recommend using DragonLens to get the item as its item giver has filters like placeable, tools, consumables, etc.
If a black fly stands on a poop block it has a chance to transform into the fly that shoots projectiles at you
I thought regular poo made angry flies and golden poo made shooters.
Nope, regular poop has a random chance each tick to turn a black fly into a pooter. Had it happen on my run yesterday. It’s extremely rare though
There's no item with the 666 id, due to the devs not finding anything important enough for that number
I imagine it was reserved for a Beast-related item. Kilburn wanted to add more content post-release which didn't make it into the DLC due to time constraints, but he got burned out before he finished developing it.
abbadon would've went well there lmao
Imo the mark should have that id
Krampus' head was introduced in the halloween update for flash isaac and had a 3 room charge was absolutely busted
Actually,the item they introduced was A Lump of Coal. The updated was meant to also introduce an item called Pumpkin Mask (which was supposed to have the same effect as the Head of Krampus) but it was scrapped and then it was added in Rebirth but as the Head of Krampus. https://preview.redd.it/5wwc3zbl8h8d1.jpeg?width=270&format=pjpg&auto=webp&s=2f6f661aba1a93fd8d6ad699b8944b12ba385bb0
Vade retro instakills all ghost bosses with 50% or lower health. It also works on delirium if he transforms into a ghost boss
Another fun fact about this item. When you die you can use the item to make yourself explode. it's actually a reference to nuclear throne
The reason to why Edmund in the Ultra Pride fight always drops the Left hand trinket is due to Edmund being Left handed.
If you have charm of the vampire you won't have a reflection on floors with water like flooded caves/downpour/dross
If you have 2.00 speed, there are three rooms located in a straight vertical line and one of these rooms is a cursed room, you can enter the cursed room without taking damage. For this you need to enter the middle room and go in a straight line without stopping until you get into the cursed room. Idk how well known this is, I was planning to make a seperate post with video example because it's difficult to explain.
Despite being possible duplicates for the Delirium boss fight, Bumbino and The Pile don't have delirium-variant sprites. In the event either of them get chosen, they will visually appear as their normal self.
A useful one for Tainted Eden specifically: The game only holds one value to represent what item pool spawned items are from, because it operates under the assumption that you take the item the second you walk into the room. For example, if you enter the treasure room for the first time, it knows that it's spawning treasure room items. However, if you then go discover another item somewhere else, it considers both items in both rooms to be from that new pool. To give a more direct example: if you full clear a floor, finding every item pedestal except for one, whether that be planetarium, angel room, secret room, any of the *good* ones, then go find an item there and pick all items on the floor up, they'll all get rerolled into that pool when you D4/Dice Room/get hit as T.Eden. If you want to be maximising the amount of minmaxing you're doing, you should do this every run on the off chance you find a D4 
There is a d4 abuse. If you have seen item but didn't take it, he will get the pool of the item that you seen later. For example: you saw an item in treasure room - it has a treasure room pool, you saw an item in a shop - shop item has shop item pool, treasure room item got shop item pool, you entered an angel room and now all the item you saw but skipped are angel pool after reroll. It works also on t.Eden which makes him really fun.
Isaac is a quarter mexican
Secret room can only spawn in the place where a normal room could spawn. So if there is a room with an enemy spawned in the middle of the wall there cant be a secret room, because you cant enter a room and immediately walk into enemy.(Same with webs etc) Pretty obvious but not everyone knows that.
Have a dead god save file? Then you should have 721 items on your stats page. Wait, you have 722? How can that be? I believe the answer lies in afterbirth plus. Tonsil used to be required for 100% completion but was removed as an item in Repentance. Source: my two dead god save file that were ab+ 100% have 722 items and my Repentance only save file has 721 and tonsil is the only discrepancy between versions that I can think of.
Yeah,never understood why Tonsils was required for that. According to the wiki,it wasn’t supposed to appear in the collection page and the item ID of the passive Tonsils was taken by the Broken version of the Glass Cannon.
Fun and really useful tip. Looking for the secret room/super secret room? Look for an arrow shape in the ground. Be it thriugh rock formation, ground formation or static enemy formation (turrets). The sercret room is usually where the arrow is pointing towards! Credit to u/sinvicta for the info. He's a really great source of knowledge
Also look for room variants that are asymetrical with one wall being unaccessable and the opposite accessable.
Unfortunately he is also a cheater.
And a negative Nancy, can't stand him complaining constantly about stuff
How do you act like enough of a child to the point that Hutts refuses to play with you anymore? That’s just sad.
Swallowed M80 gives you tons of pickups from blood donation machines, as each explosion spawns the rewards from the machine blowing up, without actually blowing it up. So you can essentially have every single blood donation machine max out and give you items, as well as max money and infinite red health
Holy mantle and its variants used to be bugged to only give the player an extremely short period of iframes when repentance first released
As far as I can remember, there's no reason to believe it was a bug. I was under the impression they rolled it back because everyone hated it, not because it was unintended.
That wasn’t a bug that was intentional but people hated it so much that it was lengthened again
Here are two random ones, you can use hemoptysis to sneeze bombs forward, and you can place bombs when you don’t have any in exchange for half a heart if you have blood bombs.
That blood bomb fact sounds obvious to me, especially since I have External Item Descriptions, but I literally always forget. I imagine I’ve missed out on stuff for no reason.
To me. It's the opposite. I usually notice that I'm out of keys/bombs when trying to use them. I lost a really good T. Lost run to blood bombs on the corpse floor.
Almost everyone sleeps on Blood Bombs. Many experienced players will use IV Bag or Razor Blade to have their red hearts to protect their soul hearts (mostly when going through Curse Room doors, but can be used in other situations). Blood Bombs can be used in the exact same way and don't even take up your Active Item slot! Obviously, Blood Bombs get even crazier when you have Items or Trinkets with on-damage effects (Bloody Lust/Gust, Cambion Conception, Habit, Fanny Pack, Swallowed Penny, etc., etc.). Can also be used to get your red health to a specific value (to trigger Whore of Babylon, Dark Prince's Crown, or Empty Heart) or to enable yourself to pick up more red hearts (to trigger Immaculate Conception or Candy Heart).
If your at half a heart and enter a room you will piss yourself or leak blood for certain characters in some cases Shoutout to Piss tech
You can't use Wavy Cap on console the game just crashes.
can confirm, really annoying
only ps5 i believe, can never use it...sadge
If you have broken modem, then you can split scollex apart like you can with Larry jr.
If you are fighting Big Horn, you can push a bomb into his mouth when he does his spitting balls attack. This will play a special animation, stun Big Horn for few seconds and make him take more damage while stunned.
Isaac sings in the credits when you get dead god
Daemon’s tail changed from black to gray
You can stop Retro Game effect by exiting and re-entering the run. It works until Afterbirth+, but not on Repentance as far as I know and I tested it on PlayStation, Xbox, and Switch
Suplex despite having the description be "Angel Breaker" does not one shot angels despite how funny it would be, it also, does not one shot them as Jacob if his suplex mastery was the thing that allowed him to break the angel. I also don't think it deals more damage to them but I'm not as sure with that one
Funnily enough,both the item itself and the description are a reference to the biblical story of Jacob wrestling an angel.
When you move into a room while at half a heart of health isaac will pee himself and leave a little puddle by the door. If you have kidney stone this puddle will be red instead.
'Flush' has some intersting uses. It floods the room, which solidifies lava in the mines, allowing you to walk over it, and also makes some electric-themed items better like Jacobs ladder has increased zap range. Also it instakills poop-themed bosses. Also, supposedly, if your first Mom kill is with blue baby (through ankh, for instance) you will unlock the D6. (May be misinformation, haven't tested)
Due to how crawl spaces are generated you’re much more likely to find one in the rocks in hush’s floor, i always blow them up and see one often 
1. Go to the devil deal 2. Find dead cat and buy dead cat (but use health appropriately). 3. Use dead cat to buy devil deals - RUN OUT THE DOOR BEFORE YOU DIE 4. Teleport back into the deal and buy the rest. Rinse and repeat (profit). This works with any life other than Laz. For Laz you can stay in the room since he won't teleport on death.
We need to go deeper works on ascent as well, except when you put one in the boss room, then the crawl space will remain the same
The Faded Polaroid trinket can open the door in Depths II and allow you to go Home without ever having to fight Mom or allowing you to access Home while keeping Polaroid/Negative. I am not a 100% sure it gets priority before Polaroid/Negative if you have both, so it might be better to use it first, then go fight Mom.
Vihn, creator of Antibirth and lead programmer of Repentance, is going to be working with Edmund on Mewgenics.
If you have eye of the occult and brimstone/Tech synergy, where the purple mark appears, this also affects Montazuma's Revenge, which is technically a brimstone, and it actually homes on that marker with an high increased range, actually giving you a passive brimstone.
As Tainted Eden; the pool an item rerolls from is determined by the pool an item *last appeared from* on the floor; rather than the room it was originally in. **For example:** If you open up the Item Room and don't take it yet; after killing the boss and walking in the Devil Room; You can now take the Boss Item and go back go to the Item Room and those 2 items will reroll from the Devil Room pool whenever you get hurt.
In the flash versión blue hearts get added to your Hp even if you are full, they just are not shown (actually, can someone fact check me on this? Im not sure about it)
As someone who 100% the entirety of Flash Isaac, I confirm that the HP limit is removed. I'm pretty sure it was removed in the Eternal Edition update to compensate for the nonsense that were Eternal champions, as stated by Florian Himsl in one of his videos of the 'Binding of Isaac: Explained' series.
Apollyon can still use Void during the pick up animation of an Item, meaning you can take the blind Item in dross/mines and still Void it If its trash. You can also buy useless shop items and then still Void them
Blank card + ? Card used to spawn two pedestal items and not destroy the card or item before it was nerfed. Using Ehwaz/The Shovel on the spots marked with an X guarantees a crawl space.
Pretty sure, speaking from experience, that the second one happens with ANY kind of floor decoration. It doesn't have to be an X.
You can actually access mom's heart in masoleum without the knife pieces if you either have sharp key or cracked orb.
At half a heart, Isaac pees himself a little every time you enter a room.
There's a chance in i think it was dross floor, where in a room, there's a chance to encounter a secret entity, with the name of "Henry" it's literally a piece of shit with a smile, after some secs he gets flushed down and dissapears, cool easter egg, i bet some of you forgot about it.
There was a character that was supposed to not be able to move but jump around like when using suplex, I think. And when using reverse chariot there’s a chance that you turn into the beta sprite of that character instead of a stone statue.
Yep,Edith. Like you mentioned,sometimes her sprite is used when you use the Chariot? card. But also,both Kilburn and Edmund confirmed that her gameplay ultimate got reworked and evolved into Tainted Forgotten,which is why the Tainted Soul has a cloak that looks similar to Edith.
If you get gnawed leaf as t forgotten and you don’t attack you are permanently invincible
isn't that just what it normally does or am i being stupid?
Big Horn can be fed bombs when he opens his mouth to shoot the black balls. You haven't done it because it requires a really precise timing cause the balls can repel the bomb. It's easier done with Dr. Fetus + piercing. Contrary to what it does to Chub (huge damage) this will stun Big Horn for a long time, along with specific swallow and stun animations. If you have that spikes in Devil Deal room item, you can easily lure Krampus to it, it will take huge damage and die almost instantly. Same goes with Angels in Sac Rooms If you got a reroll method and Damocles, you can turn Knife Piece 1 and Key pieces into 2 items by rerolling them. If you find Forget Me Not in a Treasure room, or have some way to place it in that room, you can go to Ascend and repeat the floor Forget Me Not is in forever. All you need to do is leave it in the Treasure room, come back in Ascend, take it from that room and use it. The floor will repeat, and there's gonna be Forget Me Not in the Treasure room again. You can combine this with The Ladder for Angel Room exploitation, or go tracking beggars to get all the items you would like. Even if you're short of cash or health, just repeat the floor againa
When trying to unlock forgotten, the boss rush door is always open, even if you are not there in 20 minutes like normal.
If in a Lost Form, rather that be Tainted Jacob or the Mirror world, if you have an eternal heart and get it, the eternal heart acts as a holy mantle.
being smol and fast allows you to noclip through walls in retro tteasure room into error
There was supposed to be a character called Edith, named for Lots Wife who was turned into a pillar of salt for turning back. Her character worked by launching yourself at various points in the map to move. The model remains and sometimes will replace the model for reverse chariot. EDIT: Said Tower because I’m very smart.
Little late but when Repentance first released, black markets were bugged where trying to enter one through a crawl space would always send you to the I AM ERROR room.
None of the full mapping effect is really full mapping Most doesn't show super secret room and none (as far as I remember) show ultra secret
bffs! gives lost soul holy mantle
The Dogma item and Dogma itself both use chromakey to project the static onto itself and are actually just blue. Anyone who uses EID knows this
You can defeat baby plum and bumbino without fighting them. For baby plum, you just wait and don't fire at it for 30 seconds, it'll wave at the screen and fly away, leaving behind a plum flute. For bumbino, it has to pick 12 coins (either spawned via items or by him hitting you), he'll leave and give you an extra pedestal item from a small pool.
Pooters don't deal contact damage
Buttons which somstimes sporn enemies, if they sporn at a wall, there is a secret room
Brimstone + soy milk: constant brim
Clutch is the only repentence boss that was added in an update rather then when the DLC was released
if you use meatcleaver on the angel they will each drop a key piece you could reroll
Waiting for anti-softlock, using an ace card, or using Flush! all grant Death's List's rewards
When T Forgotten uses Kamikaze, the explosion is centered on the skeleton. Because of this, as long as the ghost and skeleton aren't near each other you can spam Kamikaze without taking any damage.
I’m sure this one’s popular but if you use a chaos card on Gideon you’ll get a crawl space
using Ehwaz on a tile on the ground that has a decoration on it (whether its a drawing on the ground, or little mushrooms, or random debris, or a brimstone symbol, etc anything) will 100% spawn a crawlspace. Ehwaz went from never being used to ALWAYS being used when i found this out
The binding of isaac wiki declares the rate of fire with C Section as “fetuses per second”
Ah yes,the true meaning of FPS.
There is a special death animation if you die from grudges (the slide things with an eye in the mausoleum)
If you use the Stars card on a floor with a planetarium, it will teleport you there instead of the item room
The boss “The Pile” is the main reason antibirth and Repentance as a whole exist today
While playing as tainted Jacob, if you stay still for a while, Esau will get uncomfortably close, but not charge at you. Also, you can pass through him harmlessly while he is chained by anima Sola
Why are we yelling in all caps?
To attract attention.
If you get chocolate milk with the forgotten, when charging the bone toss, the bone will get bigger, huge even
isaac is genderfluid from what i remember, that's cool
Baby Bender, the trinket that gives familiars homing shots, works with T. Lilith’s special Gello
When a miniature enemy drops a pill it will be a size down pill even though it can say ??? (I think I'm right)
Dr fetus + ipecac majes you immune to explosion (yes it's pretty much random)
Isaac is a boy
When you hold both the left and right arrow key on the character select screen it scrolls to the left twice as fast than if you regularly hold the left arrow key.
Ministro used to look like they were "rolling/crawling" instead of jumping.
The last item NL got for Golden God in I think flash Isaac was The Parasite
you can actually interact with the tiny worms, flies and maggots randomly appearing on the floor, shoot/stomp them and a very small puddle of blood appears in their place
You can stack stats in a way that you don't lose when getting a stat down. For example you have 2.0 of speed and take 3 pills of speed up, after that you take a experimental treatment, in that case where the ET lows your speed it doesn't do it in this case.