I am also a bit relieved that it's a Supporter. Having it be an item card would A. not be useable under Item lock and B. Players could use 2-3 in a turn and it would be chaotic.Initial thoughts are that this card will run rampant. Thank goodness it's a supporter card.
Also, I just realized something. If you have a poisoned EX in the active and no way to cure it, and it will die on the next between turns stage, you could play this, save an EX, and simply put out a non-EX Basic, letting it be KO'd, and your opponent only takes one prize card. Ha.