Decidueye - DeEvelotion Spray

[Kennydawgg]

First turn Player plays Forest of Plants Evolves up to Decidueye-GX

Then uses De-Evolution spray that states "Devolve 1 of your evolved Pokémon and put the highest Stage Evolution card on it into your hand. (That Pokémon can't evolve this turn.)"

Then re-evolves during the same turn. I read that as the pokemon that deEvolved can not evolve again am I wrong? What if the player has a 2nd decidueye in his hand?

 

[PokePop]

They can't normally.
However with Forest of Giant Plants in play, this doesn't apply to Grass type Pokemon.

Game effects trump normal rules in most cases.