Proposed Canon
The Titans of Ark are godlike beings believed by the denizens of Erfworld to have created the world.
 First Appearance
The Titans of Ark are godlike beings who created Erfworld. At least three in number -- although there may be more --- and apparently serving as some kind of pantheon for the folk of Erfworld both for purposes of iconography (since they seemed to be depicted in every throne room or command centre we've seen so far) and for purposes of blasphemy ("Titan's Testes!").
They are also responsible for the creation of the Artifacts that play such a crucial role in the realpolitik of the world they created.
 Real World References
They possess a distinct resemblance, as well as demonstrating tonsorial and sartorial similarities, to a late period Elvis Presley and impersonators thereof.
For most intelligent beings within Erfworld, it is taken as a matter of faith that the Titans created the world. Furthermore, most characters seem to believe that the Titans, either directly or indirectly through their design of the world, are responsible for the seemingly spontaneous generation ( or popping ) of units, cities, and animals.summer-updates-020
 Titan's Plan
It is also widely believed that the Titans have a plan or purpose in mind in their creations, and much of the conflict around which the Battle for Gobwin Knob was based, and a more overarching conflict between Royalism and Toolism, seems to arise from disagreements over the interpretation of this purpose/plan. In order to achieve their plan, the Titans use the power of Fate and Retconjuration. Wanda believes that nothing can prevent the fulfillment of the Titan's Plan, but Jack suspects that Love may be a force even the Titans cannot control. If he is correct, then it may be that love, specifically the love that exists between Wanda and Jillian, may profoundly alter the future of Erfworld.
As there have been only three Titans seen so far, it may be possible that there is one Titan in favor of Royalism, one in favor of Toolism and a third in favor of a moderate viewpoint in which Royalism and Toolism are both equally valid and capable of peacefully coexisting.
It's apparently believed that at least some Erfworlders will live on in some form after they are croaked. The most successful warriors are permitted by the Titans to enter the City of Heroes after they die.