Anything decent out there?

for playstation one?

Yeah, playstation

D3

Borderlands

Depends on the audience. But I always refer people to a site called co-optimus. You can use check boxes to specify what you are looking for and it lists all co-op games.

Shooters seem to be non existent

Divinity original sin enhanced edition is a good one. Roommate and I have spent hours playing together

cod black ops zombie

dead nation is pretty fun too (twin stick shooter)

fighting games blazblue n mkx r fun

castle crashers had a lot of fun playing with friends

split/second car race with destruction

unreal tournament 3

Black ops 1, 2 and unreal tournament are not on ps4 unless I'm mistaken