First sorry if this is a repost.
In these runs, u let Tyrael do all the work(if u want to help its fine just dangerous). He can kill the yellow mob pretty fast and u should complete within like 2 mins.
Its simple:
1) Go to the last quest in act 4 on Inferno
2) TP to "The Crystal Colonade"
3) Run past mobs to the "The Silver Spire Level 1"
4) Talk to ghost and stand back if its Maghda & do a lil running if its Zulton
Then just repeat. This is much easier for range classes for obvious reasons, but Tyrael will kill them eventually. Also Zulton looks like he has life steal, so if u die he will regen off of tyrael. Almost fergot, I don't attempt try this if its Mira, too many adds and an over pain to kite.