Dalamadur, Serpent King

Reach, trample

You don't lose unspent mana as steps and phases end.

When Dalamadur enters, tap all untapped lands your opponents control, add many of any color equal to the number of lands tapped this way.

At the beginning of combat on your turn, creatures you control get +X/+X and you lose X life where X is the amount of unspent mana you have.