The only reason i never play pokeMMO is because you can't catch any legendary pokemon (and keep it for more than two battles)
some legendary/special pokemons are also impossible to catch and need nerds to keep the only one possible, so one of the most satisfactory thing in the entire game is gone.
when there will be a patch for catching legendary pokemons i will replay pokemmo
(also i add a little thing, if the problem is the in-game balance the question is easy, just make it unable to use it, if the problem is "It's a legendary pokemon, so it will be for only one user with more mechanics" it's pointless, you need 2 minutes to know that the casual player will NEVER have the opportunity to just have it, if the problem is even the fact that the users will use it to sell and duplicate it is easy, no possible trade and no possible sell)
