Ultron, Mechanical Tyrant

Whenever Ultron, Mechanical Tyrant enters or attacks, create a 0/0 colorless Ultron artifact creature token with "This token gets +1/+1 for each artifact you control." Then each player faces a villainous choice — that player sacrifices one non-land permanent of your choice or you may put an artifact card from your hand onto the battlefield, it becomes a 6/6 Ultron creature in addition to its other types.

If Ultron, Mechanical Tyrant is in the owner's graveyard and there is 1 Ultron artifact creatu