Lately quite a few Asian publisher (like the publishers of Dragon Nest China and C9 Korea) had such a "jump character" event.
Webzen Global is holding such an event right now:
You will be able to obtain a Level 220 Mu
character, a level 60 Archlord
character and a lvl 90 S.U.N
character along with some nice extras. The characters will be fully geared and come with some other benefits.
Basically you just need to have a webzen account, download the Game clients and install them, after those steps you just need to log in and create a new character (Note: To receive the character for Mu Online you will need to create the character on the Valhalla server).
15. February - 14 March
Take your chance to obtain free high level characters in 3 different games!
Mu Online Trailer: