The Outlaws to the End Co-Op Mission Pack Add-on for Red Dead Redemption has 10 achievements worth 100 gamerscore.
Complete a Co-Op mission.
Complete all Co-Op missions.
Complete a Co-Op mission with just 2 people.
Gold medal any Co-Op mission.
Gold medal all Co-Ops missions.
Complete a Co-Op mission without anyone dying.
Complete all Advanced Co-Op missions.
Gold medal all Advanced Co-Op missions.
Achieve a kill chain of 10 or more in any Advanced Co-Op mission.
Complete a Co-Op mission without dying.