Not confirmed for release, but whether you believe me or not is your problem!

アビスアームズ・マッドネスシェル Abyss Arms – Madness Shell
Equip Spell Card
【REQUIREMENT】 If there are no monsters in your GY, you can send 1 Sea Serpent monster from the hand to the GY to equip this card to a face-up Sea Serpent monster you control.
【EFFECT】 The equipped monster can attack twice each turn. When the equipped monster destroys an opponent’s monster by battle, inflict 300 damage to your opponent.

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