Gears of War: Judgment

This can be done with three people (Two of which must have a second controller).
Make sure all players have the Car 13 armor skin on.

Start up a Private Match > Team Deathmatch

Goal Score - 10
Number Of Bots - Fill (Makes it faster)
Bot Difficulty - Casual
Friendly Fire - Doesn't Matter

If you have the Lost Relics map pack, choose Checkout.
If not choose which ever map to your liking (Preferably a smaller one)

Kill the bot 10 times and you have your Achievement.

Join a game with 1 friend and fill with bots, one of you leave the game once you have spawned now both of you take turns to spawn back in, try to join in when a bot who is not yet wearing the skin is about to die, (it takes a few tries but my friend and i both got the 'you looking at me' and 'pendulum wars' achievements using this method because i had quit for a smoke and my mate noticed that the bot that had replaced me was still wearing my locust skin, it seemed to work nicely if we took it in turns to quit and join in again) and then they will eventually all have the skin on. Win the match. POP