Cheems, Samurai of Oreskos

Whenever you cast a Phyrexian creature or
artifact creature spell, incubate X, where
X is that spell's mana value. (Create an
Incubator token with X +1/-1 counters on it
and "{2}: Transform this artifact." It transforms
into a 0/0 Phyrexian artifact creature.)
At the beggining of each end step, if a
Phyrexian died under your control this turn,
proliferate.