Grand Pretorian

Whenever you cast a Xenomorph 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 Xenomorph artifact creature.)
At the beginning of each end step, if a
Xenomorph died under your control this turn, proliferate.