Once per turn, you can change this card's ATK to twice its original ATK. If you do this, destroy this card during the End Phase.
Rulings for Plague WolfYu-gi-oh! Card
If this card's effect is activated, it's doubled ATK is not considered to be its original ATK.
If this card's effect is activated, and it is flipped face-down and face-up again in the same turn, its effect to destroy itself will not activate during the End Phase.