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It's a Trap Raigeki (most of the time, your opponent's monsters won't have an A-Counter until your turn unless you have Kid or recently played PPV) and generates free counters on everything your opponent Summons, which is nice for turning Telepath into MST or even a sudden Brainwashing Beam, though Beam is kinda situational

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The Mewtwo ex card depicts a very different atmosphere

In a single day, buyers purchased more copies of this card than had sold in the previous five months, with an average of 33.1 copies per buyer

While it only affects artifacts and creatures, the effect is instant, and is reliable enough given the amount of both in your average Commander decks