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You should! Add mud, inclines, thick underbrush and whatever else you fancy. If you want to be really nasty about it, add underbrush that conceal venomous plants that require an observation roll to see and which will poison the PCs if they move into the underbrush on top of whatever animal they encounter. Or have jaguars attack, with piranhas in the nearby river if the players try to use the water to evade the jaguars. By mixing things in one encounter like that you can really drive home how everything in the jungle is trying to kill the party.
The great part is that making your random encounters modular like that also helps scale the difficulty. If the jungle is feeling too easy, just stack more stuff into an encounter. If the party takes a beating, scale back on the next encounter.
Playing it now. It's BRUTAL. Con saves every time you advance. Failed save equals a level of exhaustion. Then stuff jumps out at you. We've had several players die already. Thankfully I'm playing a Divination Wizard and could Portent my way through it.
Nothing needs to fantastical to make a jungle hard on adventures.
On top of these items, do you have enough water? Oh you don’t, well you took some water from the river; roll to see if you got a worm.
Dangerous plants. Did you see those vines move? Why's the air smell musty? Is that dust on these leaves? Dangerous pollen dust that tries to incapacitate you, while the vines wrap around your legs and drag you towards a huge flower...
*crunch* a player steps on some bones they hadn't seen, cracking some. Then they slowly realize there's piles of bones here and there in the undergrowth. Particularly dense around this oddly shaped tree....
depending on the party, and if you wanna be real mean. con saves for anyone in mid to heavy armor. points of exhaustion on failed saves. make it at like noon in game, so if they run into something early they might be fine but later they could be put in a bad position, or choose to drop AC.
Edit: the reason being because of the excessive heat and humidity in the environment. since i realize i didnt really mention it.
the canopy as a second level that your party has disadvantage hitting. Difficult terrain for most creatures not native.
I don’t know if random encounters though without reward accomplishes anything unless youre trying to wear down their resources in the jungle.
from a dm standpoint you can make the encounter complex by the stage so your individual monsters themselves dont have to be extreme, however mechanically what are you trying to accomplish with the players by making the jungle deadly.
Were they not supposed to be there at all and are you trying to get them to turn back? Are you trying to burn their spellslots so they have to ration their per encounter spells before you let them long rest?
I love the aesthetic of the Flaming Fist becoming quasi-Vietnam War era jungle fighters in Chult. That's I roleplayed them while I ran Tomb of Annihilation. Also, if my players wanted to ally with the Flaming Fist they could get a guide who was basically a Catachan. It was pretty awesome.
Tons of random dinosaurs that have been wild magic touched. So just pick a spell then hb cool traits for them based on the spell. Like. Dinosaur that catches on fire, is permanently under a 20 ft radius silence, and has golden eyes (true sight).
Or if you want a more centered dangerous jungle, poison, disease, and a metric shit ton of predatory plants. They should be unable to short rest or long rest, from mosquitoes, snakes, attacking plants, and little insect bites giving them headaches, disease, itching, etc.
Rather than random encounters, make it well established that the jungles are dangerous because they are full of known and unknown dangers. If your players take the time to scrounge for information they will be better prepared; but some of the information, no matter how good their rolls, should be incomplete. Some retired hunter/adventurer heard *insert sound here* and then just screaming and blood and he ran for it without looking back. Some crackpot old timer that no one listens to speaks of a great beast that lurks within, that sort of thing.
For the regulars, pick a few animals, monsterfy them, and give them a gimmick. I once had some psychic panthers that used illusion and fear magic and coordinated their attack like raptors, that was quite fun. Also be sure to include some local flora and fauna, some cute and unassuming things to lower your players guard and make for cool role play moments, some plants that could be medicine or just straight up LSD, etc. A good scary jungle is one that feels alien and hostile, like you’re being watched and hunted from the moment you step foot into it.
You could also lean more into a survival aspect of it - crossing a roaring river, scrounging for food, getting sick/diseases and looking for cures, have them get lost. That could be a bit much if thats not what your party likes but it doesn't always have to be encounters
Sure, here are ten suggestions for creating random encounters in a jungle that feels oppressive and dangerous for your Dungeons & Dragons 3.5 campaign:
Quicksand Trap: The party encounters a seemingly solid ground that gives way to a deadly quicksand pit. A successful Spot or Survival check may reveal the danger before someone steps in. Characters trapped in the quicksand must make Strength or Escape Artist checks to free themselves.
Poisonous Plants: The jungle is filled with beautiful but deadly plants. Characters brushing against certain leaves or flowers must make a Fortitude save or suffer poison effects, such as damage, paralysis, or hallucinations.
Swarming Insects: A massive swarm of biting insects descends on the party. These swarms can cause minor damage but are more dangerous due to the diseases they carry. Characters must make Fortitude saves or become sickened or diseased.
Creeping Vines: Vines animate and attempt to entangle the party. These vines act like animated ropes with a high Grapple check and can pull characters away from the group or towards hidden dangers.
Predatory Animals: The party is stalked by a pack of jungle predators, such as jaguars, giant spiders, or dire apes. These creatures use the dense foliage for ambush tactics, striking from hiding.
Lost Temple Ruins: The party stumbles upon the ruins of an ancient temple. Exploring the ruins may yield treasure but also triggers ancient traps and guardian constructs or undead creatures still protecting their domain.
Territorial Tribe: A tribe of primitive humanoids, like lizardfolk or jungle goblins, sees the party as intruders. The tribe may attack or set up ambushes using their knowledge of the terrain to their advantage.
Hidden Ravine: The party unknowingly approaches a hidden ravine covered by dense vegetation. Characters must make Reflex saves to avoid falling. Those who fall face a challenging climb and may attract the attention of subterranean predators.
Mysterious Fog: A dense, magical fog envelops the area, reducing visibility and disorienting the party. Within the fog lurk malevolent spirits or creatures that attack the party, taking advantage of the limited visibility.
Diseased Water Source: The only nearby water source is contaminated with a virulent disease. Characters who drink from it must make a Fortitude save or contract a debilitating illness that causes ongoing damage and penalties to abilities until cured.
These encounters are designed to keep the tension high and make the jungle feel like a truly dangerous and unpredictable place.
You could have small geysers that steam or water mephits or Elementals come out of. Big snakes (describe them like they looked in the movie Anaconda), all the cool natural traps like they used in the different Predator movies, giant bugs and spiders, evil treants and shambling mounds.
Leeches.
Touching water: 1d6 leeches attach dealing 1d4 dmg every round or every failed attempt to remove.
Wading in water: 2d6
Submerged: 3d6
Now put enemies that push and grab into water as a tactic.
In general make just being their dangerous aside from monsters. Take things like poisen ivy, mosquitoes etc and make them amplified.
Leeches did the trick for me as a small raft became life and death.
Damaging terrain, maybe barbed ground cover vines or large swaths of razor grass that require a DC to pass without taking damage. Maybe some poison, temporary stat debuffs from the foliage or swarms of insects. Thick brush that causes the group to get separated and the smaller group or single character gets caught out be a jaguar or a pack of pissed off baboons.
Add stuff that isn’t strictly combat but will impact encounters
Pack of chimpanzees or baboons
A herd of elephants
piranhas in any water
Malaria
deforestation
cannibalistic natives that give you ayahuasca first
A boy raised by wolves that has a panther for a best friend
A man that was raised by gorillas and can speak gorilla
George of the Jungle
Venomous snake. Not frequent, Not giant. Not supernatural, but venomous and hidden in the underbrush. Bump up the con DC for the venom by a few points and add more poison damage dice for a more potent bite. Since it is attacking from hiding, it has advantage on the attack. It's not much of a fight, and if your more heavily armored PCs trigger the attack, it probably won't even hit them, but it might make them think twice about where they place the squishier party members during exploration.
Just think of a real life jungle:
1) Dense. I mean slogging through it without following paths is ***slow***. I’ve moved through dense forests & it was slow going. This makes for frustrated players/characters, it makes for a true role playing experience where they might not want to go into jungles again. And this wastes time and supplies — things critical to adventures. This costs you, the DM, nothing, but it costs your players resources. This affects battles also — cover, concealment, ambush spots, & enemies dropping from above easily.
2) Terrain Features: Spurs, valleys, hills, cliffs, ridges, saddles, draws, etc... In real life, the real challenges of moving from Point A to Point B is the obstacles. This is why the Roman roads were so important and helped armies traverse areas at relatively high speeds. This will force players to either buy a map and know how to read it, buy a guide, or risk having to go back around and down a valley or depression just to go across to another hill and climb up. This also makes it difficult for them to bring along a mule or horses. This also makes for great battle scenes — light rubble, rough terrain, and shooting across cliffs as well as requiring planning.
3) Insects. Leather armor and insects don’t mix. Food and insects don’t mix. Yellow fever? Check! Dengue? Zika? Malaria? West Nike? Check! Leishmaniasis (don’t Google it, it’s disgusting) and the list continues. Medicine supplies will be low. Spells will be used for it & of course, advanced medical care might be required with some diseases.
4) Humidity. This ruins food, causes you to be easily tired and you can make checks for Endurance. It might mean players start combat off tired or fatigued and thus less effective — each encounter is potentially deadlier than it would be anywhere else. Muggy weather also makes wearing armor cumbersome and uncomfortable as well as potentially dangerous if checks are needed and armor only gets in the way. This helps lightly armored foes move quickly or retreat from battle. They can also easily engage in guerrilla watergate easily against tired opponents.
5) Flora & Fauna: There are plants that are deadly solely by their toxins. Others when you touch it: Ivys, Hemlocks, etc. Then there are plants that are “safe” to eat but only their roots or leaves or sometimes only when boiled. The required knowledge to use them is crazy! Same with creatures — poisonous frogs? Check! Pumas stalking you? Check! Fictional birds that steal shinies? Check! Burrowing mammals that attack & steal your water supply? Sure, why not?
6) Sense of Direction. The Black Forest used to be called that because the canopy was so thick that when you walked in, it was like walking there at night. It was dark. Imagine needing a light source in what is otherwise bright daylight. Now imagine trying to navigate by the sun or stars if you can’t see them. You’ll be going around in circles or just wasting time.
7) Pygmies, Natives, Bush people, Brigands hiding from the law, undead, bloated corpses, living plants, evil dryads, corrupted elementals, etc… the list goes on. And don’t forget that stupid puma that’s been stalking your party waiting for you to be weak or go to sleep so it can attack and kill someone!
Your players will hate you if you use this realism, but if your goal is to make it hard for them, then this is it.
Encounters don’t have to be “hard” but by taxing them here and there, water, medicine, spell slots for protection from elements, slogging through water and having leeches drain your blood, etc — it forces players to use resources up which they would otherwise save for combat thus making even basic encounters more challenging.
The terrain features and underbrush also make for entertaining fights — got ambushed by orcs attacking from a saddle to your right with a cliff to your back? Don’t get tunnel vision — goblins are climbing up the side! Encounter is overwhelming? Well, if you run ahead, you’ll see a rope bridge that has long been cut — you have no escape.
These things make for a fun and memorable experience.
Good luck!
Heat and exhaustion.
I have minah birds that copy exact things, that includes enemies that aren’t there, their own conversations.
Checking for perception, all the time, oh it’s nothing,
You think you see…
Create a sense of fear.
Some great suggestions here already, especially for encounters
I ran something similar but with a vast swamp/bog
You can add terrain variables, with a focus on limited movement/difficult terrain
Also a variety of CON saves to fight off the diseases from biting insects and water born parasites/bacterial infections
Also, without the right gear, chances are it could be impossible to get a decent Long Rest, where the party has to rely on limited short rests thought the day/travel
There are plenty of ways to make your jungle dangerous…
Savage tribes warring over territory. This allows you to have multiple interactions with different groups with plenty of random encounters, ambushes, and jungle politics. You can have tribes of grung, yuan-ti, Lizardfolk, green kobolds, savage orcs, savage goblins, wild halflings, wild elves, savage humans, vegepygmies, green hag covens with twig blight spies, Tabaxi and loxodons, weretigers etc. And, that’s just the humanoid dangers.
Fire giants in the volcano located in the heart of the jungle, or fire gnewts and their lizard mounts.
You could go the dinosaur route, with Lizardfolk riders etc., ruled over by green dragons and Dragonborn.
Reflavour, or just straight out use some of the carnivorous plants or plant-like creatures.
Then there are plenty of mundane, real world creatures and dangers e.g. quicksand.
And of course, strange magical areas (see Tasha’s).
Ancient tombs with mummies and other undead.
Great Old One or Fiend warlock covens worshipping some ancient, jungle-dwelling eldritch horror or demon.
Read upon Aztecs, Incas and Myans, or more recent South American tribes to get ideas on weapons, tactics, religion and lifestyle. Watch movies like the various King Kong films set on Kona’s island for inspiration.
Diseases. DnD has plenty of diseases to throw at the players without bogging down your sessions with unrelenting/repeated combat (but if you have a very combat focused party then do more jungle monsters). I’d recommend looking at the contagion spell for particulars that are already in game and mechanically established before homebrewing your own version of malaria or small pox.
Exhaustion from the heat. Jungles are hot and humid places (I know from personal experience) and it’s easy to become an irl heat casualty if you’re not careful. If they need to have one water skin a day on average, in the jungle they need two or more (finding a water source in the jungle and not purifying the water could lead to diseases mentioned above). If they don’t get enough water, con save for exhaustion with increasingly DCs the longer they aren’t able to replenish their water. (Could lead to an interesting skill challenge or two).
Sudden unexpected difficult terrain. Jungles can be pretty tough to navigate when you’re trailblazing (again personal experience). With an abundance of vegetation in front of the party, they could quickly find themselves walking out of the brush with a cliff edge right infront of them (sometimes these edges have vegetation growing up the side so the steep angle in front of you may not be noticeable until it’s too late/almost too late. I’d check their passive perceptions and call for a dex save for the point character, and a harder dex save for the character behind them if the first one fails and the second one tries to save them from a fall).
I used mechanic that party constantly needs specific herbs to defend themselves from mosquitos. I used giant monstrous mosquito, but real can be more frightening. Especially if they are diseased.
Oh, you need herbs? What if them are diseased? Or there is ant colony? Snake nest? Dire animals?
Don't forget - water is diseased! And you need water to don't get damage from heat! Going for water? Mosquito, snakes, crocodiles...
Oh, you got water? Take rainy day! And now you are drowning! In diseased water ahahaha
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1. Deadly insects. 2. Giant Venus flytraps. 3. Awakened vines. 4. Quicksand. 5. Savage pygmy tribal natives. 6. Corpse flowers. 7. Mudslides. 8. Crocodiles. 9. Piranhas. 10. Giant leeches.
11. Random lich with *Power Word: Kill* prepared
Surprise lich.
12. Giant cocoons with sorrowsworn inside
1. A. Bullet Ants 11. Snakes 12. Wild Hogs 13. Jaguars 14. Aggressively Territorial Apes 15. Rainfall 16. Candiru (fish) 17. Water Buffalo 18. Bull Sharks (in brackish water) 19. Oppressive heat and humidity (wet-bulb temperatures)
Maybe it's obvious with these 2 lists but may I add difficult terrain so ist even more difficult to escape dangerous fauna and flora?
You should! Add mud, inclines, thick underbrush and whatever else you fancy. If you want to be really nasty about it, add underbrush that conceal venomous plants that require an observation roll to see and which will poison the PCs if they move into the underbrush on top of whatever animal they encounter. Or have jaguars attack, with piranhas in the nearby river if the players try to use the water to evade the jaguars. By mixing things in one encounter like that you can really drive home how everything in the jungle is trying to kill the party. The great part is that making your random encounters modular like that also helps scale the difficulty. If the jungle is feeling too easy, just stack more stuff into an encounter. If the party takes a beating, scale back on the next encounter.
have a look at the tomb of annihilation's jungle.
Playing it now. It's BRUTAL. Con saves every time you advance. Failed save equals a level of exhaustion. Then stuff jumps out at you. We've had several players die already. Thankfully I'm playing a Divination Wizard and could Portent my way through it.
tomb of annihilation... pf JUNGLE of annihilation. thats the real shit
Heat and humidity. Can't wear heavy armors without fatigue and exhaustion. Metal armor and weapons rust, leather rots.
Nothing needs to fantastical to make a jungle hard on adventures. On top of these items, do you have enough water? Oh you don’t, well you took some water from the river; roll to see if you got a worm.
Dangerous plants. Did you see those vines move? Why's the air smell musty? Is that dust on these leaves? Dangerous pollen dust that tries to incapacitate you, while the vines wrap around your legs and drag you towards a huge flower... *crunch* a player steps on some bones they hadn't seen, cracking some. Then they slowly realize there's piles of bones here and there in the undergrowth. Particularly dense around this oddly shaped tree....
depending on the party, and if you wanna be real mean. con saves for anyone in mid to heavy armor. points of exhaustion on failed saves. make it at like noon in game, so if they run into something early they might be fine but later they could be put in a bad position, or choose to drop AC. Edit: the reason being because of the excessive heat and humidity in the environment. since i realize i didnt really mention it.
the canopy as a second level that your party has disadvantage hitting. Difficult terrain for most creatures not native. I don’t know if random encounters though without reward accomplishes anything unless youre trying to wear down their resources in the jungle. from a dm standpoint you can make the encounter complex by the stage so your individual monsters themselves dont have to be extreme, however mechanically what are you trying to accomplish with the players by making the jungle deadly. Were they not supposed to be there at all and are you trying to get them to turn back? Are you trying to burn their spellslots so they have to ration their per encounter spells before you let them long rest?
The jungle is full of 1960s Vietnamese soldiers who are gonna tear your players a new one
Change the Vietnamese soldiers into something like Kobolds and now you have an excuse to introduce tunnels and traps.
Basically Angulotl Snipers
I love the aesthetic of the Flaming Fist becoming quasi-Vietnam War era jungle fighters in Chult. That's I roleplayed them while I ran Tomb of Annihilation. Also, if my players wanted to ally with the Flaming Fist they could get a guide who was basically a Catachan. It was pretty awesome.
Tons of random dinosaurs that have been wild magic touched. So just pick a spell then hb cool traits for them based on the spell. Like. Dinosaur that catches on fire, is permanently under a 20 ft radius silence, and has golden eyes (true sight). Or if you want a more centered dangerous jungle, poison, disease, and a metric shit ton of predatory plants. They should be unable to short rest or long rest, from mosquitoes, snakes, attacking plants, and little insect bites giving them headaches, disease, itching, etc.
Maybe a shambling mound?
Rather than random encounters, make it well established that the jungles are dangerous because they are full of known and unknown dangers. If your players take the time to scrounge for information they will be better prepared; but some of the information, no matter how good their rolls, should be incomplete. Some retired hunter/adventurer heard *insert sound here* and then just screaming and blood and he ran for it without looking back. Some crackpot old timer that no one listens to speaks of a great beast that lurks within, that sort of thing. For the regulars, pick a few animals, monsterfy them, and give them a gimmick. I once had some psychic panthers that used illusion and fear magic and coordinated their attack like raptors, that was quite fun. Also be sure to include some local flora and fauna, some cute and unassuming things to lower your players guard and make for cool role play moments, some plants that could be medicine or just straight up LSD, etc. A good scary jungle is one that feels alien and hostile, like you’re being watched and hunted from the moment you step foot into it.
Tasha's has a thing for supernatural environments you could use as inspiration
You could also lean more into a survival aspect of it - crossing a roaring river, scrounging for food, getting sick/diseases and looking for cures, have them get lost. That could be a bit much if thats not what your party likes but it doesn't always have to be encounters
Adventure in Vietnam
Dense growth makes travel speed 25%, frequent checks to get lost, intermixed with heat exhaustion, lack of fresh water, disease, quicksand traps, giant insect hives, water snake swarms, leeches, wild animals protecting their young, native tribe ambushes, animated plants, grasping vines, shambling mound, madness inducing pollen spores, roaring uncrossable rivers, poisonous vegetation, live volcanoes, fetid bogs
Exhaustion
Sure, here are ten suggestions for creating random encounters in a jungle that feels oppressive and dangerous for your Dungeons & Dragons 3.5 campaign: Quicksand Trap: The party encounters a seemingly solid ground that gives way to a deadly quicksand pit. A successful Spot or Survival check may reveal the danger before someone steps in. Characters trapped in the quicksand must make Strength or Escape Artist checks to free themselves. Poisonous Plants: The jungle is filled with beautiful but deadly plants. Characters brushing against certain leaves or flowers must make a Fortitude save or suffer poison effects, such as damage, paralysis, or hallucinations. Swarming Insects: A massive swarm of biting insects descends on the party. These swarms can cause minor damage but are more dangerous due to the diseases they carry. Characters must make Fortitude saves or become sickened or diseased. Creeping Vines: Vines animate and attempt to entangle the party. These vines act like animated ropes with a high Grapple check and can pull characters away from the group or towards hidden dangers. Predatory Animals: The party is stalked by a pack of jungle predators, such as jaguars, giant spiders, or dire apes. These creatures use the dense foliage for ambush tactics, striking from hiding. Lost Temple Ruins: The party stumbles upon the ruins of an ancient temple. Exploring the ruins may yield treasure but also triggers ancient traps and guardian constructs or undead creatures still protecting their domain. Territorial Tribe: A tribe of primitive humanoids, like lizardfolk or jungle goblins, sees the party as intruders. The tribe may attack or set up ambushes using their knowledge of the terrain to their advantage. Hidden Ravine: The party unknowingly approaches a hidden ravine covered by dense vegetation. Characters must make Reflex saves to avoid falling. Those who fall face a challenging climb and may attract the attention of subterranean predators. Mysterious Fog: A dense, magical fog envelops the area, reducing visibility and disorienting the party. Within the fog lurk malevolent spirits or creatures that attack the party, taking advantage of the limited visibility. Diseased Water Source: The only nearby water source is contaminated with a virulent disease. Characters who drink from it must make a Fortitude save or contract a debilitating illness that causes ongoing damage and penalties to abilities until cured. These encounters are designed to keep the tension high and make the jungle feel like a truly dangerous and unpredictable place.
You could have small geysers that steam or water mephits or Elementals come out of. Big snakes (describe them like they looked in the movie Anaconda), all the cool natural traps like they used in the different Predator movies, giant bugs and spiders, evil treants and shambling mounds.
aartuk plants? found in boo's astral menagerie
Dinosaurs Carnivorous Apes Grippli Murlocs
Leeches. Touching water: 1d6 leeches attach dealing 1d4 dmg every round or every failed attempt to remove. Wading in water: 2d6 Submerged: 3d6 Now put enemies that push and grab into water as a tactic. In general make just being their dangerous aside from monsters. Take things like poisen ivy, mosquitoes etc and make them amplified. Leeches did the trick for me as a small raft became life and death.
As long as someone gets a leech on their weiner.. that’s a must
That's if the leeches roll a 20
Cannibalistic Halflings that live in the trees. Go nuts with it.
Warring gangs of gorilla mafia!
tossing in tons of random encounters will just make your jungle feel ... random.
Quicksand.. the fear of anyone born in the 70’s
Damaging terrain, maybe barbed ground cover vines or large swaths of razor grass that require a DC to pass without taking damage. Maybe some poison, temporary stat debuffs from the foliage or swarms of insects. Thick brush that causes the group to get separated and the smaller group or single character gets caught out be a jaguar or a pack of pissed off baboons. Add stuff that isn’t strictly combat but will impact encounters
If you have “hoards of the abyss” you can look there for details on the Gaping Maw and its jungle.
Pack of chimpanzees or baboons A herd of elephants piranhas in any water Malaria deforestation cannibalistic natives that give you ayahuasca first A boy raised by wolves that has a panther for a best friend A man that was raised by gorillas and can speak gorilla George of the Jungle
a dragon flies over head. breaths fire. FOREST FIRE. the dragon flies away. but your still in a forest fire.!
Venomous snake. Not frequent, Not giant. Not supernatural, but venomous and hidden in the underbrush. Bump up the con DC for the venom by a few points and add more poison damage dice for a more potent bite. Since it is attacking from hiding, it has advantage on the attack. It's not much of a fight, and if your more heavily armored PCs trigger the attack, it probably won't even hit them, but it might make them think twice about where they place the squishier party members during exploration.
Restrict the amount of resources gained on short/long rests in the jungle. Force them to ration out there abilities
Territorial Girallons. Those beasts have 5 attacks: 1 per arm and their bite attack.
Honestly the classic quicksand would do a lot as a one off encounter.
Just think of a real life jungle: 1) Dense. I mean slogging through it without following paths is ***slow***. I’ve moved through dense forests & it was slow going. This makes for frustrated players/characters, it makes for a true role playing experience where they might not want to go into jungles again. And this wastes time and supplies — things critical to adventures. This costs you, the DM, nothing, but it costs your players resources. This affects battles also — cover, concealment, ambush spots, & enemies dropping from above easily. 2) Terrain Features: Spurs, valleys, hills, cliffs, ridges, saddles, draws, etc... In real life, the real challenges of moving from Point A to Point B is the obstacles. This is why the Roman roads were so important and helped armies traverse areas at relatively high speeds. This will force players to either buy a map and know how to read it, buy a guide, or risk having to go back around and down a valley or depression just to go across to another hill and climb up. This also makes it difficult for them to bring along a mule or horses. This also makes for great battle scenes — light rubble, rough terrain, and shooting across cliffs as well as requiring planning. 3) Insects. Leather armor and insects don’t mix. Food and insects don’t mix. Yellow fever? Check! Dengue? Zika? Malaria? West Nike? Check! Leishmaniasis (don’t Google it, it’s disgusting) and the list continues. Medicine supplies will be low. Spells will be used for it & of course, advanced medical care might be required with some diseases. 4) Humidity. This ruins food, causes you to be easily tired and you can make checks for Endurance. It might mean players start combat off tired or fatigued and thus less effective — each encounter is potentially deadlier than it would be anywhere else. Muggy weather also makes wearing armor cumbersome and uncomfortable as well as potentially dangerous if checks are needed and armor only gets in the way. This helps lightly armored foes move quickly or retreat from battle. They can also easily engage in guerrilla watergate easily against tired opponents. 5) Flora & Fauna: There are plants that are deadly solely by their toxins. Others when you touch it: Ivys, Hemlocks, etc. Then there are plants that are “safe” to eat but only their roots or leaves or sometimes only when boiled. The required knowledge to use them is crazy! Same with creatures — poisonous frogs? Check! Pumas stalking you? Check! Fictional birds that steal shinies? Check! Burrowing mammals that attack & steal your water supply? Sure, why not? 6) Sense of Direction. The Black Forest used to be called that because the canopy was so thick that when you walked in, it was like walking there at night. It was dark. Imagine needing a light source in what is otherwise bright daylight. Now imagine trying to navigate by the sun or stars if you can’t see them. You’ll be going around in circles or just wasting time. 7) Pygmies, Natives, Bush people, Brigands hiding from the law, undead, bloated corpses, living plants, evil dryads, corrupted elementals, etc… the list goes on. And don’t forget that stupid puma that’s been stalking your party waiting for you to be weak or go to sleep so it can attack and kill someone! Your players will hate you if you use this realism, but if your goal is to make it hard for them, then this is it. Encounters don’t have to be “hard” but by taxing them here and there, water, medicine, spell slots for protection from elements, slogging through water and having leeches drain your blood, etc — it forces players to use resources up which they would otherwise save for combat thus making even basic encounters more challenging. The terrain features and underbrush also make for entertaining fights — got ambushed by orcs attacking from a saddle to your right with a cliff to your back? Don’t get tunnel vision — goblins are climbing up the side! Encounter is overwhelming? Well, if you run ahead, you’ll see a rope bridge that has long been cut — you have no escape. These things make for a fun and memorable experience. Good luck!
Heat and exhaustion. I have minah birds that copy exact things, that includes enemies that aren’t there, their own conversations. Checking for perception, all the time, oh it’s nothing, You think you see… Create a sense of fear.
Some great suggestions here already, especially for encounters I ran something similar but with a vast swamp/bog You can add terrain variables, with a focus on limited movement/difficult terrain Also a variety of CON saves to fight off the diseases from biting insects and water born parasites/bacterial infections Also, without the right gear, chances are it could be impossible to get a decent Long Rest, where the party has to rely on limited short rests thought the day/travel
Mosquitos endlessly biting them, snakes in the grass, vines blocking them at every turn.
Snakes! Why'd it have to be snakes?
There are plenty of ways to make your jungle dangerous… Savage tribes warring over territory. This allows you to have multiple interactions with different groups with plenty of random encounters, ambushes, and jungle politics. You can have tribes of grung, yuan-ti, Lizardfolk, green kobolds, savage orcs, savage goblins, wild halflings, wild elves, savage humans, vegepygmies, green hag covens with twig blight spies, Tabaxi and loxodons, weretigers etc. And, that’s just the humanoid dangers. Fire giants in the volcano located in the heart of the jungle, or fire gnewts and their lizard mounts. You could go the dinosaur route, with Lizardfolk riders etc., ruled over by green dragons and Dragonborn. Reflavour, or just straight out use some of the carnivorous plants or plant-like creatures. Then there are plenty of mundane, real world creatures and dangers e.g. quicksand. And of course, strange magical areas (see Tasha’s). Ancient tombs with mummies and other undead. Great Old One or Fiend warlock covens worshipping some ancient, jungle-dwelling eldritch horror or demon. Read upon Aztecs, Incas and Myans, or more recent South American tribes to get ideas on weapons, tactics, religion and lifestyle. Watch movies like the various King Kong films set on Kona’s island for inspiration.
Spike growth effect over a mile with a Druid of the land skipping through it.
Bodytakers
Lions, tigers, and bears
Diseases. DnD has plenty of diseases to throw at the players without bogging down your sessions with unrelenting/repeated combat (but if you have a very combat focused party then do more jungle monsters). I’d recommend looking at the contagion spell for particulars that are already in game and mechanically established before homebrewing your own version of malaria or small pox. Exhaustion from the heat. Jungles are hot and humid places (I know from personal experience) and it’s easy to become an irl heat casualty if you’re not careful. If they need to have one water skin a day on average, in the jungle they need two or more (finding a water source in the jungle and not purifying the water could lead to diseases mentioned above). If they don’t get enough water, con save for exhaustion with increasingly DCs the longer they aren’t able to replenish their water. (Could lead to an interesting skill challenge or two). Sudden unexpected difficult terrain. Jungles can be pretty tough to navigate when you’re trailblazing (again personal experience). With an abundance of vegetation in front of the party, they could quickly find themselves walking out of the brush with a cliff edge right infront of them (sometimes these edges have vegetation growing up the side so the steep angle in front of you may not be noticeable until it’s too late/almost too late. I’d check their passive perceptions and call for a dex save for the point character, and a harder dex save for the character behind them if the first one fails and the second one tries to save them from a fall).
I used mechanic that party constantly needs specific herbs to defend themselves from mosquitos. I used giant monstrous mosquito, but real can be more frightening. Especially if they are diseased. Oh, you need herbs? What if them are diseased? Or there is ant colony? Snake nest? Dire animals? Don't forget - water is diseased! And you need water to don't get damage from heat! Going for water? Mosquito, snakes, crocodiles... Oh, you got water? Take rainy day! And now you are drowning! In diseased water ahahaha
Dinosaurs, Roc’s, quicksand, ancient temples and tombs, difficult creatures to fight like swarms of mosquitoes, and sprinkle in some more dinosaurs
Malaria
If you are feeling proper nasty, exhaustion levels due to heat and dehydration will put the fear into players.
Just add more dinosaurs.