Something like the Battle Pyramid but rather than wander around in a maze, you wander around a preset area with "wild" Pokemon that you have to catch and raise, but each Pokemon has some preset moves
You can also find a few TRs scattered around to help you customize, but they'll be guarded by Trainers
Each floor has a boss Trainer, and after clearing 50 floors, you challenge the leader
The levels will scale accordingly, but you cannot revive any of your fallen Pokemon, you have to catch some more (and your limit will be how many Poke Balls you have) or just try to go on with whoever's left
There will be no PC either, once you catch six, you're set with those six and if you catch another you just swap out one of the six and that one gets let go
You will go in without any Pokemon, but none of the trainers will battle you unless you have something to battle with, and your first catch will always be guaranteed
Finally, each floor will have a few areas that suggest a certain type, like some trees and forests will signify that there are Grass and Bug type Pokemon in the nearby grass patches, while some ponds and waterfalls will have nearby grass patches for Water types, and you'll also be allowed to fish in the area
These areas will change every floor, giving each floor at least a few types to work with; what's in 'em will be Pokemon with predetermined sets but which ones will show up will be random
tl;dr: Battle Pyramid but you have to catch the Pokemon and train 'em to progress
