My gjallerhorn came from a purple during a public event on patrol on the moon. Loot cave taught us purple engram's come off of anything anytime. Let's get the strike over and on to the next. PS strike reward from rushing Mida x 4 4th horseman Ice breaker x 2 Thunder lord Finishing the strike to get the actual reward is better than wasting time in hope of a reward and breaking down 100 green engram's later.