Gruntageddon

Gruntageddon is an achievement in Halo: The Master Chief Collection. It is unlocked by killing 1,000 Grunts. The achievement is worth 10 gamerscore.

Trivia

 * The title is a portmanteau of "Grunt" and "Armageddon", suggesting that the Grunts effectively undergo a world-shattering disaster by your hands.