yugioh cyber end dragon deck Malefic - YMP1-EN004 - Secret Rare inflict piercing battle damage Cyber End Dragon: The Decisive

You can only use this effect of "Mistar Boy" once per turn.

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Artifact Reality Twist Cumulative upkeep (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) If tapped for mana, Plains produce , Swamps produce , Mountains produce , and Forests produce instead of any other type

It's important to know a small detail of this card's text and ruling: The card states that: "[...] your opponent cannot activate Spell / Trap Cards until [...]"

Sure, it looks like a great addition to the old school variants of Blue Devotion, but its ability will rarely come up by turn two