Sea Serpent [Alpha Edition] Island Mountain When Mulldrifter enters the battlefield

When Mulldrifter enters the battlefield

Set: Modern Masters Type: Enchantment Rarity: Rare Cost: {2}{R} Nonbasic lands are Mountains

Set: Commander Anthology Type: Land Rarity: Uncommon {T}: Add {C}

−3: Target opponent's life total becomes 10

Set: Kaladesh Inventions Type: Artifact Creature — Construct Rarity: Mythic Cost: {4}{R}{R} First strike

Sea Serpent [Alpha Edition] Island Mountain When Mulldrifter enters the battlefieldSet: Alpha Edition Type: Creature Serpent Rarity: 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?