Warhammer 40,000: Dawn of War II
73 Achievements
2000
Xbox 360
Allies to the Chapter
Complete 15 missions in Co-Op in Dawn of War II.
25
How to unlock the Allies to the Chapter achievement in Warhammer 40,000: Dawn of War II - Definitive Guide
Eternal, Hybridchld
Start a cooperative mission by inviting a friend at the Campaign main menu. You will control two squads while your friend controls another two (with inverted colors to distinguish). Complete 15 mission to unlock this.