I've posted this before on a couple sites over the past couple years, but no one can ever help me or seem to remember what it's called. I played it at my cousin's house sometime in like 2004. There's a good chance it came out sometime in the 90s.
-It's for the PC
-Over-the-top style shooter, like Zombies Ate My Neighbors style
-Regenerating enemies, in order for them to stop regenerating you need to destroy the regen points
-Very arcady
-Supported multiple players per one PC, I remember I used WASD, my cousin used IJKL or arrows or something, and my other cousin used a USB gamepad
-Similar to the kind of cheap download-only games that we got a lot of this gen, but I'm pretty sure it was a retail game
-Levels were short
-It had "2000" or "3000" or something like that in the title
I'm honestly starting to believe it doesn't exist or (more likely) my memory is foggy and it never actually had some of the elements I remember it having, because I've looked at quite a lot of games and I'm 100% sure that none of them are what I remember it being. I've also thought that maybe it didn't have a retail release at all and was just a flash game.