SCP 5031 Murder Monster

SCP 5031 doesn't untap during your untap step.
Whenever SCP 5031 blocks or is blocked, it
phases out. Untap it.
Whenever SCP 5031 becomes the target of a spell
or ability, it phases out. Untap it.
At the beginning of each end step, if SCP 5031 is
phased out, it phases in.
{x}{x}, {t}: create X food tokens
Whenever you sacrifice a food, untap SCP 5031