you need
-IP rights... that is all inclusive, both the engine and server technology, and the copyrighted property, such as character designs, legends, settings, place names, etc. In perpetuity so that NCsoft couldn't revoke them at a later date to start their own competing COx property.
-Infrastructure tools... the neccessary hardware and software required to do maintenance on the game. this includes dedicated testing machines, dedicated development machines, and licenses to powerful software for 3d modeling, audio recording, etc.
-Rackspace... That is a physical location for your servers. When COH started they had locations both in the US and Europe, with plans to launch a third korean server... but eventually the korean version of the game was axed, and the european servers were physically transfered to America. Such a location needs to be a data center which is both safe from weather and tectonic events, and has reliable uptime and a very high degree of bandwidth service. That is to say you're not going to go down to your local two guys in a garage and run an international videogame server/social network.
-Programming staff... let's face it, sooner or later you're either going to want to upgrade the game (for instance, windows 8/8.1/9 compatibility, linux steam box) or you're going to run into a glitch that ammateur skills can't fix, or a security hole which has thus far not been recognized. So you need a staff of people experienced in the maintenance and upkeep of a game running several virtual or physical servers, a website, an email, etc.
-Lights-on staff... the moderators and security team. these people aren't JUST for keeping the trolls at bay, they also play an important part in mitigating player issues between the community and the programming staff, negitating disputes between players, and policing things like intellectual property violation (COH's strict "no homage" rules which kept DC/Marvel/Image from suing on the grounds that COX could be used for violating their IP.)
-Data keeping... You'll need a way to back up user accounts and more. Even if you rely on a system like Sentinel or Icon to allow users to back up costumes at home, you still need a way to archive months, if not years worth of server-side data. usser accounts, preferences, server-side maps and balancing adjustments... if a server ever physically goes down, or if an update turns out to be bad, you have to have copies of all data, stored separately from your servers and your produciton equipment, to restore from. This is usually two locaions, one directly on site for daily or weekly backups, and a long-term off-site backup in a physically separate location for security purposes.
-optionals... If you are feeling brave, you can do all this yourself... but you may still want to take out a type of insurance, be it legal insurance against lawsuits (such as a lawyer on retainer) or physical insurance on the hundreds of thoudsands of dollars of hardware and software listed above. Additionally any bank notes, holding corporations to keep the IP protected, any benefits you provide your employees (Affordable Care Act, perks, etc) Plus of course the various legal perils from operating any kind of buisness, such as someone, government, law enforcement, court injunction, etc, swooping in to cease your hardware, or less savoury types of payouts you'd think better left to fiction.
As you can see, it's an extensive and daunting list to try to tackle, not to mention expensive.