Crackleburr

this + Painter's Servant, Red Elemental Blast/Pyroblast, Jaya Ballard, Combust, Magnetic Mountain, Chaotic Backlash = Hell for you opponent.

Other than that, it has great potential. Just figure you drop a Steam Hopper turn 1, Riverfall Mimic turn 2, this turn 3 making Riverfall Mimic 3/3 unblockable, turn 4 activate the tapping ability and deal 3dmg anywhere; then activate the untap ability to bounce a creature of theirs and attack. Effectively you could deal 11 dmg to them buy turn 4, 12 or 13 if you attacked turn 2 and 3 with the Stream Hopper. And turn 5 could be a kill if they don't throw a wrench into your engine

crackleburr + clout of the dominus + two hybrid of red and blue creatures = incinerate + oblivion ring for 4 xD

I play this in casual and it works pretty good, though I find the "tap two red creatures" part pretty hefty. So instead a slap a quicksilver dagger on him, that's when he really works well and cheap, even more so if you have niv-mizzet in play with him.