[playbox12]

I would say learn a language like C, I think it's also possible with C# but why bother. Then as stated above you need to learn the in's and out's of reverse engineering which is a pain, also memory hacking and hooking is very importand. Look at sa-mp as a hack, it hooks and changes memory adresses to let the game behave a certain way. Normally if you create a game from scratch and decide to also support multiplayer you would not do this. However in sa-mps case they don't have acces tot he source, so this is the only way. (go ahead correct me if I made a mistake).