Rampant Gnasher

Trample
{2}{g}{g}: Monstrosity 2 (If this creature isn't monstrous, put 2 +1/+1 counters on it and it becomes monstrous.)
When Rampant Gnasher becomes monstrous, target opponent sacrifices an artifact and 2 creatures. If they do not control an artifact, they must sacrifice a land. If they do not control a land, they take 4 damage.