>>30189589The sheer amount of single-stage shit-mon, or the amount of totally useless pokemon introduced in general.
How fucked up the distribution is; all of the cool unique pokemon are limited to very specific areas, with all the boring stuff sticking around throughout the game.
Z-Moves as a concept.
The story is very bland and predictable. The only interesting part is Lusamine, but you only see her twice. None of the legendaries are even remotely involved in the story or even explained, besides Tapu Koko.
The UB subplot revolves around the Looker and the International Police instead of Ultra Beasts/Space.
You never go back to Ultra Space and only ever see that one pathway leading to Lusamine.
Trials are piss-easy.
The Battle Tree being literally just the Battle Chateau except with Red and Blue slapped on the end. Even the Battle Resort in ORAS was better, the Battle Tree is just the fucking tree itself, an IV guy, and the BP shop.
The region feels very small and there wasn't much to explore.
Guzma, and Team Skull as a whole, did nothing besides take over that one town, and literally only served to be a red herring for the obvious "Aether is corrupt" twist.
"Kanto is close enough to travel to any time!", despite the fact that you can't go to Kanto. I mean, it's not my favorite region, but ANYTHING to extend gameplay would've been nice.
Lillie and Lusamine are gone forever after you beat the game and they're literally never coming back.
Type: Null/Silvally is shit.
I could go on but that about sums up my main complaints.