Skorn's Mana Barbs

{w}{w}{b}{b} Suspend 4 & Split Second
Whenever a player taps a land for mana this card deals 1 damage to that player. If the land is Otherworldly you lose no life.
When destroyed all players sacrifice half of
the lands they control. If Skorn is in play
Otherworldly lands destroyed this way
are shuffled into its owners library.