Several factors influence Vivid Voltage card values: card condition (mint cards worth 3-5x more), rarity (holographic and rare cards command higher prices), first edition status, PSA/BGS grading scores, and market demand for specific Pokemon
Try TCGplayer to find valuable cards, there's almost always a less expensive alternative
Show and Tell is the best spell to "cheat" gigantic threats like Emrakul, the Aeons Torn or Omniscience into play
A few other payoffs for this strategy include Ashiok, Wicked Manipulator and Ashiok, Nightmare Muse for additional finishers
Find the English versions of Shrouded Fable cards in Night Wanderer.
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