The Magic 2012 Expansion Add-on for Magic: The Gathering - Duels of the Planeswalkers 2012 has 3 achievements worth 50 gamerscore.
Defeat Jace, Jace and Jace as the Archenemy in a campaign game
Host a match on Xbox LIVE as the Archenemy
Defeat Gideon, Garruk and Koth as the Archenemy in a campaign game