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
I have held these loose opinions for as long as these mechanics have been things (Just realising I predate cycling in Magic, not just in age, but actually playing, has made me feel real old)
(As will I
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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