HeilMary

I don't really have a favorite, but i can suggest a few.
Aces Wild:Crazy beat him up that is quite fun. High skill ceiling that can really make it quite fun and challenging. Local Coop.
Shank 1 and 2: A brawler at its core but with the ability to shift around your "moves" (switch weapons). You can make some sick combos.
Guacamelee: Released a few months ago. It's alot of fun with colorful graphics and satisfying moves. I believe it supports coop and has a few rpg (upgrades) elements as well.
Castle Crashers: Quite old and fun. But play with friends and with a controller. It's basically a 4 player coop brawler and is quite fun (with friends).

I keep em. My logic being that it's like a book, once you read it you keep it and look at it every once in a while to look at you favorite parts and scenes. Except that VNs have CGs and OSTs instead of books which are just words.