Yawgmoth, The Ineffable

As an additional cost to cast this spell, sacrifice
any number of artifacts. Yawgmoth, The
Ineffable enters the battlefield with a +1/+1
counter on it for each artifact sacrificed this way.
When Yawgmoth, The Ineffable deals combat
damage, return a permanent card with lesser or
equal mana value from your graveyard to the battlefield tapped.
"Life was, servitude is."