Alright, finally done with the Chaos Dungeon (I think? I mean i beat the old king, that's it right?) and i got a few questions:
1-What does the Drink Me potion/Eat Me cake do? I know you can use the first one to get a scene with Mary. Is there any other point?
2-Similar question, what's the Rabbit Key for? There's a hidden room next to the busts where you can use it, with a bunch of rabbits in it. Where do i go? I tried killing all the rabbits and nothing happened
3-Where do i find the hotel poseidon event? i only know it exists because there's a scene with red hood in the reminiscence room
4-how do i get the Alice (Service) scenes? i assume you have to start a new run and head straight to the Tree elevator room. just want some confirmation
The old king is the point of the dlc, but there are more bosses that have lore, a few you've seen before as well waiting for you in the chaos dungeon, not to mention upgrades of rings that can help improve your build. pretty sure it goes down to depth 19, at least that's where it stopped for me.
The drink me potion shrinks you if you drink it in a room before the headhunting beast fight, it allows you to access the pond of blood early.
The rabbits are literally only for soul farming like in the first game.
The hotel event is right after god fish has an area blocked off where if you step in it he kills you inside the ship, you gotta go around it and then go up to what looks like a dead end, then try clicking on the walls with no vines, there will be different versions depending if you have RRH unlocked or not.
and for the fourth question see question 1, they're for the same thing.