It was continued in Speed Duel GX: Duelists of Shadows and included the Deck themes Elemental HERO, Evil HERO, Red-Eyes, Archfiend, Vampire, Amazoness, Cyber, Cloudian, Dark Scorpion, and Dark World
(Twice as much if youre playing a 7-year-old who cant and wont learn.) Or, if you feel like youve already spent far too much money on this nonsense already, you can pretty much replicate everything from the Battle Academy yourself
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The GW Heliod deck in Modern routinely plays Spike Feeder as a backup combo to Walking Ballista, which greatly increases the chances of having at least one loop going by turn three or four