Flip a coin. If heads, this attack does 20 more damage and the Defending Pokémon is now Paralyzed.You may do 20 more damage. If you do, this Pokémon does 20 damage to itself.
The Defending Pokémon is now Poisoned. If the Defending Pokémon tries to attack during your opponent's next turn, your opponent flips a coin. If tails, that attack does nothing.