This post says that you can't do that, however, I don't see why you would not be able to. Take Torterra for example: Since "LV. X" is not part of the name but just the Level, Torterra LV. X's real name is just Torterra. That's why we can only have 4 Torterra and Torterra LV. X combined in a deck. So since the Level Up text says to put the LV. X card onto Torterra, Torterra LV. X == Torterra and therefore should fulfill the requirement. Is there somewhere in the rulebook that says you can't Level Up a Pokémon more than once? That would seem stupid since this is trying to mimic the video game where Pokémon Level Up, and obviously a Pokémon in the video game Levels Up more than once. Since X is a variable, meaning the next Level, why can't the new X equal X + 1? Does anyone know if this has actually been confirmed by Japan (since, no offense to them, they don't always have to rule with the logic of things, but on how things are "supposed" to be) or if it has just been ruled this way cause it would be "weird" to have the same card on top of itself? Unless there is a part in the rulebook that says you can't, or Japan has said we can't, then all the requirements on the cards are met, and therefore should be able to happen. If neither the rulebook nor Japan has overridden what the card text says, and yet we are still not supposed to do what the card lets us do, then how are we supposed to be able to read the cards and make a correct ruling, when the cards aren't always right?