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 3 of the 4 banshees in the level Halo. It is worth 10 Gamerscore points.[1]
It is represented by a banshee with a 3 above it inside a reticule.
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