Alduin, Eater of Worlds

Flying, deathtouch, haste
When you cast Alduin from the command zone, sacrifice any number of lands, then destroy that
many lands for each opponent. For each land put
into a graveyard this way, put a +1/+1 counter on Alduin and draw a card.
{b}{b}{r}{r}, {t}: Return target land and target Dragon from your graveyard to the battlefield tapped.
{x}{r}{r}, {t}: Deal X damage to each non-Dragon creature and each opponent.