From Destinypedia, the Destiny wiki
The Mountaintop is a Legendary Grenade Launcher acquired from the Crucible pinnacle Quest of the same name given in Season 5 of Destiny 2. It is the second Kinetic grenade launcher in the game after The Militia's Birthright, and has effectively zero range drop-off with shells experiencing virtually entirely linear travel, technically making it the most accurate grenade launcher in the game.
[Fireteam leaders: Do not advance on the Wall. Fall back to the Ridgeback District.]
[Shaxx! Do you copy?]
He risks a look over his shoulder at their home, the place they call the Last Safe City. Not burning. Not yet. Gritting his teeth, he reloads.
[Shaxx, your orders are to retreat.]
[This battlefield is not your stage, Shaxx! This is not about glory!]
His fireteam doesn't hesitate.
[Shaxx! For the final time: Fall! Back!]
As the six of them crest the Wall, Shaxx cuts the feed.
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