Gilford the Lightning [DR04-EN242] Secret Rare Xyz Monster but its original ATK becomes

but its original ATK becomes 0

Set: Astral Pack 6 Card type: Normal Monster Rarity: Common Attack: 1300 Defense: 700

When a monster(s) you control is targeted for an attack or by an opponent's card effect (except during the Damage Step): You can destroy all cards your opponent controls

but the opponent's monster was not destroyed by the battle: You can banish that opponent's monster

Gilford the Lightning [DR04-EN242] Secret Rare Xyz Monster but its original ATK becomesSet: Dark Revelation Volume 4 Card type: Effect Monster Rarity: Secret Rare Attack: 2800 Defense: 1400 You can Tribute 3 monsters to Tribute Summon this card. If you do, destroy all monsters your opponent controls.