Lithomancer's Focus

A combat trick built for a board where the killing was being done by colorless creatures. The +2/+2 is the obvious half; the prevention clause is the design's whole reason for existing. By voiding all damage from colorless sources, this turns a one-mana pump into a hard answer against any threat whose damage carries no color: the towering Eldrazi it was first aimed at, but also artifact creatures, manlands that tap for no color, and constructs of every stripe. Block an enormous attacker, swing the toughness math with the buff, and watch its damage simply not happen, regardless of how large that number was. Most defensive tricks ask you to guess at the size of the incoming hit and pay accordingly; this one ignores size entirely so long as the source is colorless. The catch is that the prevention is dead weight against the bulk of the field, where attackers are colored and the clause does nothing but pad the card's text. Pointing a trick this precisely at one slice of the creature pool means accepting it does half its job most of the time. It reads as a humble pump spell right up until a colorless attacker walks into the block and dies for free, at which point it has functioned as conditional removal disguised as a buff.