Hearthpwn

You can hit legendary with almost any Zoo variant, even the original deck design. And this one is stronger. The deck doesn't do all the work for you. You actually have to know what you are doing.

Argent commander?

lovin' the king mukla. he's really underrated.

since i dont have mukla what should i use?

same question here.. maybe leeroy?

I run leeroy but I don't think he is a good choice.  he duplicates your doomguard ability and really is only viable as a finisher since he summons his own likely death.  I would say scarlet crusader fits better in the slot and doesn't move the curve higher, she sticks in most matchups and will do likely six damage.

I run blood knight it has saved me many a match and works well with argent squires or mirror match warlocks and pallys

Arcane Golem. Or Harvest Golem.