Pokémon MMO 3D is a Massively Multiplayer Online Role Playing Game in the Pokémon theme. Trainer and pokemons are controlled with third-person camera. Fight in Real-time battles, play with your friends and the community. Currently in alpha, download on the webSite pokemon-mmo-3d.com
To catch a pokémon you need fight it and when it reaches zero HP.
Recall your pokémon.
And use a ball with your trainer to throw it on. (press C)
If you are lucky you will catch it, else it back to fight and you will have to repeat the process.