You have to distinguish between what the card is when not in play and when it is in play.
Very different.
When not in play, it is a Level Up card. Not a Basic. Not an Evolution.
You can't search for it with a Mentor or a Prom Elm's Training Method.
When it is in play, it is in play along with the card of the lower level Pokemon that it leveled up.
It is consided the same stage as that Pokemon while in play.
So, while in play, <Insert a Basic LvX here> is a Basic. Therefore you can't attach those Special energy cards to it.
