Your Hardest 360 Achievement.?

Question

Seriously on Gears for me. It isn't hard, it just takes time which I don't have.

Answer 1

in halo 3, getting 5 sticks in one game. thats hard. i haven't gotten it yet.

Answer 2

Id have to say the hardest was Halo 3 Double Laser kill in free for all ranked to get my last achievement for it

Longest was assassins creed getting the last of the 100 flags in the main opened area of the map linking all the towns/cities