I was inspired to look at "loss of life" cards. Black was the obvious winner in options, with no other color coming close. I decided to eschew any life gaining, minimize defense, and focus solely on loss of life. In doing so, I created a deck with 27 creatures and 13 non-creature cards, all except one of which can cause loss of life, and that exception (Mindcrank) responds to loss of life. I would probably do well either to trim the high end or to add some mana enhancements, but there feels like enough to work it at the low end. The 18/10/4/7/1 curve averages a paltry 2.08, and a number of cards at the 1- and 2-spot can combine to cause heavy losses quickly and early.