Gem-Knight Master Diamond [DT07-EN083] Ultra Rare Phantom Darkness if a "Sinister Serpent" exist

if a "Sinister Serpent" exist in your Graveyard

Sacrifice Crystal Vein: Add {C}{C}

Each Expansion Set 15: Battle Enhanced contains:

dealt damage

Set: Beta Edition Type: Creature — Human Assassin Rarity: Rare Cost: {1}{B}{B} {T}: Destroy target tapped creature

Gem-Knight Master Diamond [DT07-EN083] Ultra Rare Phantom Darkness if a "Sinister Serpent" existSet: Duel Terminal 7 Card type: Fusion Effect Monster Rarity: Ultra Rare Attack: 2900 Defense: 2500 3 "Gem Knight" monsters Must first be Fusion Summoned. This card gains 100 ATK for each "Gem " monster in your Graveyard. Once per turn: You can banish 1 Level 7 or lower "Gem Knight" Fusion Monster from your Graveyard; until the End Phase, this card's name and original effect become the same as that banished monster's.