From Destinypedia, the Destiny wiki
Posterity is a Legendary Hand Cannon that can be acquired from the Disarmament encounter in the Deep Stone Crypt Raid. Opening the Disarmament Spoils chest, accessible after defeated Taniks, the Abomination, has a chance to drop this weapon.
The weapon is eligible for randomized perks, but the following is the curated roll. The curated roll currently does not drop from the raid.
The following are the randomized perks for the weapon.
List of appearances