Private Servers

Does anybody here owns a private server like cabal,mu online,maples story,etc.
Because I really wanna know what thintgs to be needed or softwares in order to establish my own private server.

These are most of the time illegal. If you notice properly, these are big game companies and they usually wait till the private servers get quite big and they end up suing them. Anyway, you would need a source. For example, you need the Odin source for Maple Story.