If You complete the indicated task You'll get the allotted gamerscore.
Rummy Buff (30) - Earn over 50,000 Total Points.
Merciless (25) - Win 1 Player Match hand against one player by 50 or more points.
Rummy Master (25) - Win 5 games/matches in each single player mode, and 25 player matches.
Rummy Shark (20) - Win 10 matches or games in Single Player.
On a Roll (20) - Win 20 rounds by going Gin in any game mode.
Gutsy Gin Guru (20) - Win 1 round without drawing from the discard pile.
Well-Suited (15) - Win 1 round with cards including deadwood from only one suit.
Close Cut Match (10) - Win 1 round by Undercut.
Gin Winner (10) - Win 1 round by going Gin.
Rummy Bunch (10) - Finish a 4-player game of Gin Rummy in any mode on Xbox LIVE.
Setting Champ (10) - Win 1 round with only sets.
Knock-out (5) - Win 1 round by Knock.