Prime Engrams were introduced in Destiny 2 with the Forsaken expansion in 2018 as a key way to gain powerful gear and raise power level. Dropped by tough enemies during activities, the glowing purple engrams had to be taken to a Cryptarch to be decoded. Their arrival sound became familiar to regular players through repeated strikes, Gambit and patrol play, and clips of lucky drops spread across gaming videos and streams. The cue is now reused outside Destiny as a shorthand for any rare, high value reward appearing.