Good lord My friend got one from a strike from a random drop that randomly gave him an exotic engram that randomly was a primary that randomly decrypted into a 310 Zhalo. I've been grinding the same way he does (heroic strike playlist) for much longer than him. He didn't earn his Zhalo. Nobody can earn a Zhalo. It is a completely random weapon. You can earn a Touch of Malice, an Exotic sword, or the Chaperone, because those are guaranteed quests you can get and complete. Saying you "earned" a weapon is complete bullcrap. Even if you got it off of a Shade of Oryx in the raid or a raid boss, that isn't earning a weapon if you can only randomly get it from anywhere. There's no way to prove getting it there from just a taken champion that goes down in 5 seconds.