Ruling Shaymin Lv.X question

[Team Rose]

This might be obvious but doubt has been risen at my last league day.

I'm using my grass deck and my opponent KOs my active (according to plan). I then send out my basic shaymin to replace my KOed active. Then my turn starts, and I level up my active shaymin with "revenge seed" shaymin lv.x. Since my opponent KOed one of my grass pokemon last turn I claim "revenge seed" activates, but my opponent claims it doesn't activate because shaymin lv.x was not in play during my opponents last turn. I reply with "The card doesn't specify that it has to be in play at the time of the KO". We ask the league leader and he takes my opponents side (I should mention he is not a professor).

I've had this deck for months and this is the first time anyone questioned the way I play "revenge seed" shaymin lv.x. So my question is does revenge seed work on the turn I put it in play as long as one of my grass pokemon was KOed during my opponents last turn?

 

[banuffin]

You are correct in your conclusion as to how Shaymin's Poké-BODY works. His Poké-BODY simply checks whether or not one of your {G} Pokémon was KO'd from damage from your opponent's attack during your opponent's last turn. Shaymin LV. X does not have to be in play at the time the KO occurrs in order for his BODY to provide the attack boost.

 

[DNA]

A check of game state (as that is what Revenge Seed is) doesn't mean that the owner of that ability has to be in play at the time that the Knockout happened. All it requires is that one of your Grass Pokemon was knocked out last turn, and it was. Revenge Seed then triggers.

This also applies to other similar cards, such as the Toxicroak G [Promo] Poison Revenge attack (Toxicroak G doesn't need to be in play at the time of the knockout to get the damage bonus).