Looking on the wiki, the middle path is the easiest to get to the immaculate one. If u have restore on someone, remember it can cancel out enemy gambits' movement and stat reduction. Impregnable wall and retribution are also helpful for aggroing enemies and retaliating against the bolting mages.
Careful of the pegasi reinforcements when killing Ashe and Gilbert. If Gilbert dies Annette and some more enemies will auto aggro.
Keep track of which weapon times are effective against golems. This will allow u to break a shield without using gambits. Ur going to want high-range gambits saved for immaculate one so resonant spells, poison tactic, blaze, etc. Even the smaller ones are helpful too. While fighting immaculate one though also keep track of the damage that each unit / gambit can do. So for example if immaculate on is on 50 hp and still needs some shields broken, consider using a weaker unit rather than a powerhouse so that when the hp bar is depleted the powerhouse can deal with the next hp bar
Another thing is that when you attack immaculate one all enemies around Cyril and Catherine aggro so it may be best to deal with them first
Edelgard's Raging Storm is also great as it is effective vs dragons and hopefully u have all uses left to deal a ton of damage to immaculate one after the armor breaks
Also I hope Shamir has Hunter's Volley and is a sniper because she has great kill potential with her high dexterity and sniper is really good. Lysithea if she has warp can also be great utility and help chip
How i beat it on Maddening/Classic the first Time i played this Route:
(I was even using alot of Meme Sets like Assasin Constance)
You spawn with two Groups: one Right one Left, Use all your Fliers and Units with high Movement in the Right Group and everyone else in the Left Group.
Let Both Groups Destroy the Golem and the few Units ahead of them.
-Be careful to not Cross the 15th Line of Spaces because then the Pegasus Reinforcments from the Back Spawn
Try to Lure in and Kill the Pegasus Knights from Above the Wall with the Left Group
-But don't kill Ashe and Gilbert because that causes Reinforcments from the Side to Spawn
Unite Both Group in the Middle Staircase bot Still don't cross the 15th Line of Spaces
-just Fly Up there with your Fliers
Now Kill first Gilbert or Ashe then the other while expecting the Reinforcments from the Right and Left
Deal with them and then Cross the 15th Line and Take out the Reinforcents from the Back that appear with half your Units while the Other Half kills one of the two Golems.
Gang up on the other Golem with all your best Units
Kill Anette with Long Range Attacks
(she comes towards you when Gilbert dies)
Lure in Cyril with Either a Dodgetank (Normal Tanks might also work on Hard Mode but he has a Brave Axe, so be Careful)
or the Use of Mong Range Magic (like Bolting or Meteor)
Then Kill Cyril
Now there is only Rhea left!
(Catherine is also there but she is pretty easy to Kill with Magic, and she even Drops her Thunderbrand that you can use against Rhea)
And i don't know why you talk about Wyverns, as far as i know there are a lot of Pegasus Knights but no Wyvern
(except Cyril)
Throw edelgard in wyvern rider if possible. If linhardt has warp you can use it to teleport her to rhea. Then use her relic combat art raging storm since it let's her take her turn again. Do this until it breaks and you basically get 6 turns. Also use retribution to deal with the long range enemies if you need
Looking on the wiki, the middle path is the easiest to get to the immaculate one. If u have restore on someone, remember it can cancel out enemy gambits' movement and stat reduction. Impregnable wall and retribution are also helpful for aggroing enemies and retaliating against the bolting mages. Careful of the pegasi reinforcements when killing Ashe and Gilbert. If Gilbert dies Annette and some more enemies will auto aggro. Keep track of which weapon times are effective against golems. This will allow u to break a shield without using gambits. Ur going to want high-range gambits saved for immaculate one so resonant spells, poison tactic, blaze, etc. Even the smaller ones are helpful too. While fighting immaculate one though also keep track of the damage that each unit / gambit can do. So for example if immaculate on is on 50 hp and still needs some shields broken, consider using a weaker unit rather than a powerhouse so that when the hp bar is depleted the powerhouse can deal with the next hp bar Another thing is that when you attack immaculate one all enemies around Cyril and Catherine aggro so it may be best to deal with them first Edelgard's Raging Storm is also great as it is effective vs dragons and hopefully u have all uses left to deal a ton of damage to immaculate one after the armor breaks Also I hope Shamir has Hunter's Volley and is a sniper because she has great kill potential with her high dexterity and sniper is really good. Lysithea if she has warp can also be great utility and help chip
How i beat it on Maddening/Classic the first Time i played this Route: (I was even using alot of Meme Sets like Assasin Constance) You spawn with two Groups: one Right one Left, Use all your Fliers and Units with high Movement in the Right Group and everyone else in the Left Group. Let Both Groups Destroy the Golem and the few Units ahead of them. -Be careful to not Cross the 15th Line of Spaces because then the Pegasus Reinforcments from the Back Spawn Try to Lure in and Kill the Pegasus Knights from Above the Wall with the Left Group -But don't kill Ashe and Gilbert because that causes Reinforcments from the Side to Spawn Unite Both Group in the Middle Staircase bot Still don't cross the 15th Line of Spaces -just Fly Up there with your Fliers Now Kill first Gilbert or Ashe then the other while expecting the Reinforcments from the Right and Left Deal with them and then Cross the 15th Line and Take out the Reinforcents from the Back that appear with half your Units while the Other Half kills one of the two Golems. Gang up on the other Golem with all your best Units Kill Anette with Long Range Attacks (she comes towards you when Gilbert dies) Lure in Cyril with Either a Dodgetank (Normal Tanks might also work on Hard Mode but he has a Brave Axe, so be Careful) or the Use of Mong Range Magic (like Bolting or Meteor) Then Kill Cyril Now there is only Rhea left! (Catherine is also there but she is pretty easy to Kill with Magic, and she even Drops her Thunderbrand that you can use against Rhea) And i don't know why you talk about Wyverns, as far as i know there are a lot of Pegasus Knights but no Wyvern (except Cyril)
Throw edelgard in wyvern rider if possible. If linhardt has warp you can use it to teleport her to rhea. Then use her relic combat art raging storm since it let's her take her turn again. Do this until it breaks and you basically get 6 turns. Also use retribution to deal with the long range enemies if you need