Also, for MP, take a look at Robot Roller-Derby Disco Dodgeball. It's a content-heavy instagib multiplayer arena shooter with an emphasis on score (in some mode

Also, for MP, take a look at Robot Roller-Derby Disco Dodgeball. It's a content-heavy instagib multiplayer arena shooter with an emphasis on score (in some modes), and some interesting takes on attack, defense, and movement. If you're up for some traditional Arena FPS, take a look at Reflex, Xonotic, and UT4. Or just boot up Quake 3 (or Quake Live) again. I almost forgot Half-Life Deathmatch. That's still an absolute blast to play.