It is indeed a legit game. I'm a Lv.29 Martial Artist (at Lv.30 you do the aging quest to become an adult and choose your master class)
You can be a Human Martial Artist / Spiritualist, Namekian Warrior / Dragon Clan (healer) or a Majin (Majin Buu race) Ultimate / Chef? I forgot lol, but yeah it's a fun game. The downside is you either need to buy your account, or make it yourself. Which is pretty tough. You should definitely check it out though, it's by Netmarble, in Korea. I'm actually the maker of the English patch that's used and supported by an admin at one of the English community forums.
The English patch isn't anything fancy, you just take one of the game files that has all the Korean text and you start translating it. A majority of it has been translated by myself and the help of other users, the admin of the English community forum made a program that allows easier patching, because before the patch would have to manually be updated by me or him. The system requirements are on http://dbo.netmarble.net for the site to run as intended it's best to use I.E. I use I.E Tab extension on my Chrome.
Edit: The translated game file doesn't include quests or skills or items though. It does however translate 90% of the entire UI like options, selections, NPC choices, NPC names, etc.
The forum also has Skill Calculators and Interactive Maps