Shonen Jump Alpha Promo - Superdreadnought Rail Cannon Gustav Max

It's release is unknown.

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JUMP-EN062 Superdreadnought Rail Cannon Gustav Max Earth/Machine/Xyz/Effect 10 ATK/DEF 3000

Effect:
2 Level 10 Monsters
Once per turn: You can Detach 1 Xyz Material from this card; inflict 2000 damage to your opponent.