Zyflair said:
Read the person that just ninja'd you and you'll find where it's been answered.
Furthermore, if you actually read the rulebook, it tells you:
"A Pokémon LV. X can’t be played on a Pokémon that evolved that turn or on a LV. X already in play. (For example, if you evolved your Pokémon to Torterra this turn, you could not play Torterra LV. X on that Pokémon.)"
Is that enough proof for you?
Okay! I wasn't against you or anything, I just wanted evidence which before you didn't give as for this question opinions/assumptions aren't valid unless backed up with solid evidence.
Anyway, I got it: you
can't level up a Lv.X
Also, the guy who ninja'd me (whatever that means) said "
a Lv.X is the final stage of evolution of a pokemon line", which is incorrect.