Necrohydra

[Jonnyfive]

Necrohydra

Level 7/ Water / (Zombie/Effect)

Increase this card's attack by 1000 every time it is special summoned from the graveyard. This card cannot attack the turn its attack is increased by this effect. When this card gains attack points because of its effect, the new attack becomes its original attack. When this card attacks it is changed to defense position at the end of the turn.

ATK 2000/ DEF 0

[Ririkun]

This card is invalid and is impossible. The game will not keep track of it's attack, even if you list it in the card, you can't just break the rules. If it gets special summoned more than once, it will not stack, like first time 3000 atk, then 4000 atk, it will always be 3000 atk because it's atk will reset to 2000 once it leaves the field. I hope you understand that.

[CrabHelmet]

This card is invalid and is impossible. The game will not keep track of it's attack' date=' even if you list it in the card, you can't just break the rules. If it gets special summoned more than once, it will not stack, like first time 3000 atk, then 4000 atk, it will always be 3000 atk because it's atk will reset to 2000 once it leaves the field. I hope you understand that.

[/quote']

 

Card effects can give cards more "memory" than they would normally have if necessary. For example, cards usually forget everything when they're flipped face-down, but cards like Guardian Sphinx and Stealth Bird will remember whether they've used their effect yet anyhow. Why? Because the card says it remembers, and if the card says it remembers, it remembers. Similarly, Twin-Headed Behemoth will remember whether its once-per-duel effect has been used even if it is flipped face-down, then destroyed, then removed from play, then shuffled into the deck, then drawn, then discarded, and then Special Summoned by Call of the Haunted. Cards don't normally remember that sort of thing, but if a card effect says a card remembers, the card remembers.

 

tl;dr: Existing cards prove you wrong.