Here is the full list of all 12 Marvel Puzzle Quest: Dark Reign achievements worth 1,000 gamerscore.
I Love it When a Plan Comes Together
Complete "Prodigal Sun".
Hit a max level with any character.
Complete "ISO-8 Brotherhood".
Complete "Thick As Thieves".
Complete "The Hunt".
Complete "Unstable ISO-8".
Match an eight of a kind.
Complete "Prologue".
Defeat Juggernaut
Collect 15 covers for any character.
Get a 9 chain combo.