Aware there's a sale on this week.
Still have a save just before the final boss if you just need the co-op achievement (with enough time to get all 10 pictures) but can help you all the way through if you need it.
Games With Gold for dummies
Mutual assistance for the following games' achievements:
Need For Speed: Hot Pursuit (MP including the DLC),
Gears Of War 1 (Hardcore Campaign, Dom run one of them),
Battleblock Theater (Open for trading, 3 out of 10! Co-op, etc.),
Might & Magic: A Clash Of Heroes (MP stuff),