Creator of the Great Liberator

Powerstones you control tap for an additional {c} and can cast nonartifact spells.
{3}- Sac 2 artifacts you control and create a Piece
of Karn, on your upkeep if you control five or
more "Pieces of Karn" exile this card and re-enter
the battlefield as the Planeswalker "Karn Newly Liberated"
"A Piece of Karn is a 0/5 with defender Token
with +1/+0 for every Piece of Karn you control"
-This card can be your commander