History of Apostate

Apostate is a Legendary Arc Sniper Rifle with a Rapid-Fire Frame, introduced in Shadowkeep (Game Wiki: Season 8).

Overview

Notable perks: Rapid Hit, Fluted Barrel, Extended Mag, Accurized Rounds and Shield Disorient, which Destinypedia calls strong in PvE.

Acquisition

Destinypedia says to complete waves in Altars of Sorrow. The Destiny Game Wiki specifies a guaranteed drop from the Nightmare of Taniks boss chest in Altars of Sorrow, or a possible drop from the Pit of Heresy.

The two opened sources (Destinypedia and the Destiny Game Wiki) disagree on some details such as the season of introduction, and neither states whether the weapon can be crafted or has an Adept version, so those are treated as not stated. Bungie's in-game source text reads "Random Perks: This item cannot be reacquired from Collections."