[@Rekker] I wouldn't use the word "limitless," it helps better to envision these as Endgame/Max Level RPG characters. Extremely powerful, possibly the most powerful living thing on their world, but not omnipotent.

PvP will probably occur at some point, but the rest of the RP will involve the characters encountering and dealing with that which exists outside of space and time, which should be a robust challenge even for the powerful characters we'll be playing. 

However, it won't be all new frontiers. There is more to ruling than conquering, after all. As they say, enjoy the war, the peace will be terrible.