Kill 20 enemies in a row while driving a vehicle.

This achievement can be earned on the mission Cliffhanger on Recruit difficulty.
After you've boarded the snowmobile you will want to take it a bit slower than you normally would going down the mountain so that the enemies can catch up to you. Just keep on holding down the left trigger to take out the enemy snowmobiles. You don't want to go to a complete stop as the helicopter will start shooting you.



This achievement is worth 10 gamerscore.