Sacrifice is an extremely prevalent theme in the game; with the two protagonists losing their life because of it. Ku sacrifices herself to save Ori from shriek, and is immediately impaled off-camera because of it. However, she is later revived due to Ori’s sacrifice. Ori embraces Seir and becomes the new spirit tree to revive Ku and save Niwen, bringing an end to ori’s life. Kwolok also sacrifices themselves to kill the foul presence.
Half-way into the game you can talk to a lizard named Motay who will reveal he has secretly been following and watching you but you never actually see him and he acts as your stat tracker.
there is a quest where a cat-like species (moki) character's family dies, although you don't actually see them die. And in one part of the map you can see petrified mokis everywhere in the background. Theyre not actually cats, but they look a lot like it
In an extremely late game cutscene, a large sand worm is crushed to death during a chase scene while trying to devour Ori
In addition to this, crusher traps are scattered throughout the map- but ori will just puff into smoke if they come into contact
[Spoilers] One of the boss fights features a frog ally that has been possessed by an oily spaghetti-like creature. It is physically wrapped around him and forces him to fight.
It is revealed in a cutscene that the main antagonist wasn’t allowed to play with their peers as a child because of their physical disability. If they weren’t disabled, then they wouldn’t have gone evil, etc etc - that ol’ trope.