If You complete the indicated task You'll get the allotted gamerscore.
Perfect Team (35) - Win a 6 vs 6 Xbox LIVE round without any teammates getting knocked out.
Perfect Player (25) - Win a match on Xbox LIVE without getting knocked out.
20 MVPs (25) - Be the MVP player 20 times in any mode.
50 Wins (25) - Win 50 games in any mode.
Arena Master (15) - Play at least once on each arena.
Double KO (15) - Knock out 2 or more opponents at once using the Shooter's Super Shot.
Party Time! (15) - Play in a game with eight players on Xbox LIVE.
Ranked Veteran (10) - Win at least 5 ranked matches on Xbox LIVE.
Line Master (10) - Play at least once with each line and each ground variation.
Ball Master (10) - Use each ball in a game at least once.
Destroyer (10) - Knock out opponents using each character's Super Shot.
Finisher (5) - Knock out an opponent using a Super Shot.