Leave It Where It Lay
From Halopedia, the Halo wiki
Leave It Where It Lay
Leave It Where It Lay is an achievement in Halo: Combat Evolved Anniversary that is awarded for completing the level Two Betrayals without picking up any other weapons on Legendary difficulty.[1] It is represented by a MA5B assault rifle with a "forbidden" sign over it.
It is worth 25 Gamerscore points.
The easiest way to earn this achievement is to start the mission on Legendary with the Bandana Skull active. As the Skull grants infinite ammo, one never needs to grab another weapon, so the achievement simply becomes a matter of remembering not to pick anything up.
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