No-Fly Zone
From Halopedia, the Halo wiki
Grenadier
No-Fly Zone is an achievement in Halo: Combat Evolved Anniversary that is awarded for destroying three of the four Banshees in the level Halo. It is represented by a Banshee inside a reticule, with "3" above it.[1]
The achievement is worth 10 Gamerscore points.
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