Hi,

I believe a (maybe) simple way to enable wild animals fighting in the arena against humans or other beats would be to make downed wild animals "imprisonable", just like humanoids.

i shoot an animal till its lying on the ground -> i capture it (having a room with animal beds set to prisoner) done. when its healthy i can use it in the arena like any other being without having to tame it first.

i am no programmer but in my mind this should be able to work since its one of the core functions of the game with humanoids to begin with anyways...