Step 1: Load mission Fist of Crota normal difficulty on earth Step 2: Ride sparrow through mission untill you find hive doing the ritual Step 3: Kill the blade of crota (There are no requirements for the drop just kill it. Also it won't drop like silken codex or black wax once you kill it it will show up on the right side of your screen like how raid loot is given) Rinse and repeat don't get discouraged after a couple of try's, I've been helping a friend and I'm almost at the 50 kill mark.