For step 3 (kill 100 acolytes/wizards w/ void) I went into a patrol on the moon and just ran around in the temple of crota area killing acolytes. Took me 5-10 minutes For step 2 melee cursed thralls I went to the new dlc moon mission. There is an endless supply of cursed thralls right before the darkness zone. This works better with 2 people but guide them around until one is far enough away from its group, weaken it to >1/2 health and melee it. The explosion will hurt but you won't die. Take your time.