Sea Serpent [Limited Edition Alpha] Magic 2011 If the player doesn't discard

If the player doesn't discard a card this way

He craves only one commodity

Set: Kaladesh Inventions Type: Artifact Creature — Construct Mythic Cost: {4}{R}{R} First strike When Combustible Gearhulk enters the battlefield

Set: Seventh Edition Type: Land Rare Cost: {T}: Add {C}

on the other hand

Sea Serpent [Limited Edition Alpha] Magic 2011 If the player doesn't discardSet: Limited Edition Alpha Type: Creature Serpent Common Cost: {5}{U} Sea Serpent can't attack unless defending player controls an Island. When you control no Islands, sacrifice Sea Serpent. Legend has it that Serpents used to be bigger, but how could that be?