Sanctum of the Makers

{3}, {t}: you may put a land card from your hand
onto the battlefield, then draw a card.
{t}: add {c}{c}. Activate this ability only if you
control seven or more other lands.
{5}: Until end of turn, Sanctum of the Makers
becomes an X/X colorless Construct artifact
creature with trample and lifelink until end of
turn, where X is the amount of other lands you control.
Sanctum of the Makers can be your commander.