Phykus of the Horde

Phykus of the Horde enters the battlefield with a +1/+1 counter.
Whenever you cast a creature spell, put a +1/+1 counter on Phykus of the Horde.
{2}{t}, Sacrifice Phykus of the Horde: Put X 6/6 green Wurm creature tokens with trample onto the battlefield, where X is the number of +1/+1 counters on Phykus of the Horde.