Flawless Mission is an achievement in Street Brawl.
Description[]
Player must clear a rival gangs turf, start to finish, without losing a life.
Gamerscore: 10
Guide[]
You'll need to complete every stage of a mission without dying. The first stage is the easiest, you can do this in local co-op but you can't via live because it will send you back to the lobby after each stage.