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Chain Whirlwind, Mirror Force good backup cards, Chain whirlwind can get triggered by the Barrel Dragons, by BM-4 Blast Spider, Vermillion Dragon Mech, Gizmek Orochi, The Serpentron Sky Slasher, Raigeki, Mirror Force, Dark Illusion, Instant Fusion, Knightmare Cerberus, Knightmare Phoenix, Rasterliger, and also maybe when Escape From the Dark Dimension or Fiendish Chain get destroyed, when the monster that got targeted gets destroyed by battle.
A planeswalking cube
Honorable Mentions: Alchemy Otters Accident-Prone Apprentice, Indris, the Hydrostatic Surge, Tempest Trapper, and Enduring Friendship are otters created for Arena's Alchemy format and each has a digitally-exclusive mechanic
If this card attacks, your opponent cannot activate Spell/Trap Cards and monster effects until the end of the Damage Step