Effect
Target 1 face-up "Photon" monster you control; until the End Phase, it gains 700 ATK, and if it attacks a Defense Position monster, inflict piercing Battle Damage to your opponent. When it inflicts Battle Damage to your opponent this turn: You can target 1 Spell/Trap Card on the field; destroy that target.
If activating during the Damage Step, you can activate it from the start of the Damage Step until before damage calculation.
The effect "When the selected monster inflicts battle damage to your opponent's Life Points, you can select and destroy 1 Spell/Trap Card on the field" is an effect that creates a Chain Link. (You target 1 Spell/Trap Card to destroy when activating this effect.)
For the effect "Until the End Phase, the selected monster gains 700 ATK, and if it attacks a Defense Position monster, inflict piercing battle damage to your opponent," "End Phase" is read as "end of the turn." (Applied from July 10, 2014)
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