This is a quest weapon: Quest line step 1: when the wolves gambit is the daily heroic, search the top of the citadel for three weapon components. 2: take components to banshee so he can assemble the prototype. He tells you to take the weapon of fallen origin to variks to translate the enscription which reads torrent of silence prototype. 3: it is a common weapon with one perk: mutiny. "This weapon buzzes when used against its former fallen allies." Kill about 500 fallen with this weapon and upgrade the mutiny nose making it a 230 attack legendary called torrent of silence mark 2. Infuse it up to 280. Return to Variks. 4: variks tells you to prove yourself in the level 35 prison of elders and defeat Skolas. Skolas will drop an item called the elder cipher transmat core. 5: return to variks so he can fuse the weapon with the core. 6: wait until arms day ;) 7: return to variks and receive the torrent of silence exotic auto rifle.