Azusa, Destiny Found

Tapped lands you control have exalted. (Whenever
a creature you control attacks alone, it gets +1/+1
until end of turn for each instance of exalted among permanents you control.)

Whenever a creature you control deals combat
damage to a player, if it attacked alone this turn,
you may untap up to X lands you control, where
X is the amount of damage it dealt to that player.