Zombie Repeller

Zombie Repeller is a Halo 3 achievement that is gained by getting two Zombie kills in one of the Mythic Maps in either a ranked or a social playlist, added with the Title Update 2, along with 29 additional Achievements. It is worth 25 Gamerscore.

Its icon is similar to the Delicious Brains icon, with the exception that the background and stars are brown, and the skull is green and slightly mutated.

It can be achieved in the Living Dead Double EXP Weekend, Rumble Pit (currently approximately 5.91% chance of getting an Infection gametype on a Mythic map), and sometimes in the 7 on 7th Playlist.

Tips
If you're lucky enough to actually play infection on the mythic maps, then this achievement should be very easily unlocked as the only thing you have to do is kill two zombies. The easiest gametype to do this, is the Braaaains-gametype, as zombies have no shields, making them considerably easier to kill.

Related links

 * Halo 3 Achievements
 * Delicious Brains