Dora of Fate (DR2-EN215) - Dark Revelation Volume 2 Unlimited

You can only activate this card during your opponent''s turn. Select 1 face-up monster on your opponent''s side of the field. When you successfully Normal Summon a monster that is 1 Level lower than the selected monster during your next turn, inflict damage to your opponent''s Life Points equal to the Level of the selected monster x 500 points.