Overkill Medal (Halo 3)

To easily obtain the Overkill Medal, custom, social, or ranked, you should steal kills, or obtain the noobiest arsenal.

If you want the achievment (without cheating), go into a ranked Lone-wolfs match and just try your best.

The way to cheat for the achievment, go to ranked FFA, and have language set to the last language, hit x in matchmaking lobby, and select the last option, then start searching and youll find lots of people that want to gain achievments, non-legitimatly.