http://www.gamedaily.com/games/gears-of-war-2/xbox-360/game-features/gears-of-war-2-achievements/

Seems like I'll add a lot of gamerscore this Nov.

Cool some co-op acheviments

And the Horse You Rode in On- Story progression in Act 5, Chapter 1, 10

LOL that's the name of one of the chapters in the last level of the first Halo.

^ =O

Do we know if insane will be available from the get-go, or will it need to be unlocked by completing a lesser difficulty first?
Also, if it's there from the start, will the achievements stack, so finishing the game on insane will bag 300 points?

Kick 'Em When They're Down-Perform all 11 unique executions on a downed enemy, 10


Haha

I think I heard insane will have to be unlocked by beating the game on a lesser difficulty

Easy achievements. Seriously 2.0 the hardest.

I assume they will stack like last time