Seviper (52/106) [Diamond & Pearl: Great Encounters]

[P] Tail Blade (20) Flip a coin. If heads, your opponent can't play any Trainer cards from his or her hand during your opponent's next turn.

[2P] Poison Tail (30+) Flip a coin. If heads, this attack does 30 damage plus 30 more damage and the Defending Pokemon is now Poisoned.