[TOMT][video game]Possible ps1 game where there's a giant tentacle/octopus monster thing inside a building?

Or it might have been a PS2 game. i think it was like a 3rd person action game, might be a shooter. there was a level where you're in a giant building and there's a monster inside with its tentacles sprawling through all the rooms and you can't see the body for a lot of it you're like exploring the building and trying to find a way to it?