Fair Play (written)

[Landrisce]

Fair Play

Normal spell

This card is activated when duel begins sending it from deck or hand to banish zone neither player can win with special conditions card effects

[Flash Flyer - Sakura]

"Banish zone" isn't an official term; you'd want the following fix:

 

"Activate this card at the start of the Duel by banishing this card from your hand or Deck. Neither player can win the Duel by card effects."

 

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But really, outside maybe Exodia or something (remind me if Final Countdown stall or something is relevant nowadays; I doubt it), no one even uses card effects to win (they just win via OTKs and stuff). Though, with that in mind, I do remember that Spiral Serpent got a retrain and does have a Trap support which enables an alt. win, but I don't know how well it's doing. 

 

This should not be activating from the Deck, but even if you were to make this a regular Continuous Spell or something, it's only suitable for VERY limited cases.