Keeper of the Souls

Non-artifact creatures you control have undying.
Whenever a non-artifact creature you control dies, and it has a +1/+1 counter on it, Choose one;
-Exile target land you control. Return that creature to it's owner's hand.
-Exile that card from your graveyard. Put a +1/+1 counter on Keeper of the Souls.
Transformed: Keeper of the Fields