Look Out for the Little Guys

Look Out for the Little Guys is an Achievement in Halo: Combat Evolved Anniversary and Halo: The Master Chief Collection.

Halo: Combat Evolved Anniversary
In Halo: Combat Evolved Anniversary the achievement is unlocked by completing the level Two Betrayals on Heroic difficulty or higher, without killing a single Grunt. The achievement is represented by a Grunt's face on top of a purple octogon, and is worth 10 Gamerscore.

Halo: The Master Chief Collection
In Halo: The Master Chief Collection the achievement is unlocked by completing Two Betrayals on Legendary difficulty only. It is represented by a screenshot of Derelict in The Master Chief Collection for the Xbox achievement, and a Grunt face for the Steam icon. It is still worth 10 Gamerscore.

Tips
Attempting to unlock this achievement playing solo is both very difficult and frustrating. A far easier method is to play cooperatively and have the other player kill all of the Grunts. In the absence of another person, players can complete the level on another profile leaving their own controller untouched. This also ensures the player does not accidentally kill a Grunt and nullify their progress. If the player has not already earned them, this method can also potentially unlock the Leave It Where It Lay, Standard Operating Brocedure, Brovershield and Bro Hammer achievements.