Pokémon Catch System...?

[Rukishou]

HI! I'm making a new pokémon game, the Marble version!!
I'm in need of a pokémon battle system and, of course, a pokémon catching system!

Requirements for catching pokémon:
•Got at least one pokéball in your bag.
•The pokémon isn't already caught by a trainer.
•the pokémon isn't too strong so that it won't get caught.

Thinking of the last point of the requirements I alsdo need to say that the pokémon should be able to get out of the ball like in a real pokémon game.

If you're not saure how the sytem works, play some pokémon!