>>53556142Ok I understand what you're asking for... you want proof of an existing card with an ability that can be activated whenever it's in play (besides cards like Lumineon V that only activate when played), but only once as long as it's on the field.
Unfortunately, most card abilities follow the same pattern:
1) They stay on unless shut down.
2) They have to be activated and can be used as often as you like.
3) They have to be activated and can only be used once per turn.
3) They have to be activated and can only be activated in a way that you couldn't reactivate the ability unless you remove the card from the field.
The #3 characteristic is seen in cards like Lumineon V, where it goes from hand to bench. It doesn't need to specify once per turn, because there is no "normal" way of removing the card from your bench. The same goes for cards like Ho-oh V (discard to bench), Ditto V (bench to discard), and Eevee from Astral Radiance (evolves itself).
Pokemon has no sort of "counters" to indicate the permanent usage of an ability. The abilities that are once per turn are kept track of every turn, and are reset upon starting your next turn. Those that aren't once per turn are quite obvious because the action isn't easily reversible (i.e. hand to bench).
So yeah, no cards currently exist (that I know of, and I searched pretty deep...).
