Honestly its the combination of the deck thinning and divine favor that makes it really messed up. If they play Dr 6 and then follow with its an instant win. Also makes me rage when I'm playing patron and their secrets take forever to proc.
It's just insane they thought this was ok. No other card does this much, while still having playable vanilla stats. Draws 5 cards, and gives you 5 mana as a battlecry with practically no stat penalty? It's absolutely nuts, and makes Dr Boom seem balanced. Should have at least been their legendary, but they can run 2 of them? Ugh. And the good vanilla stats make drawing the 2nd one not even that bad.