Bubbles, the Amorphous

When Bubbles, the Amorphous enters the battlefield, each player sacrifices an artifact. Bubbles enters the battlefield with a +1/+1 counter for each artifact sacrificed this way.
When Bubbles dies, create X 0/1 green Ooze creature tokens with "Sacrifice two Ooze creatures: Return a card called Bubbles, the Amorphous from your graveyard to your hand." where X is Bubbles' power.