Since the earlier design of One And Done conflicted with black cards in an existing deck, I decided it was time to try a different take: monocolor trample/deathtouch. The average cost is a little higher this way, but the mana assist requirement is not as great because there is only one color. A total of 16 creatures have (and another 5 can get) deathtouch (one by pairing up). Another 14 cards grant trample. With Lure, a boosted creature with deathtouch and trample could wipe out the entire defense and deal damage on top of it all. At 11/14/13/2, the curve is quite nice, though there are a few ongoing costs possible, so a couple of mana elves are there to take care of it (or early needs). This gives a fairly low 2.15 average.