In the universe everything exists in pairs. Both even and mirrored, but with alterations to keep them unique. World A and World B are the greatest examples of this: one being the home to the Final Fantasy and the other being a world devoted to the Dissidia.
However, this also means that there are two wars between the God of Chaos and the Goddess of Harmony. One taking place in World B, and who's story you may already know. The other, however, takes place in but another world.
In this world things appear as a combination of other worlds instead of a single, copied world. For each world a warrior is summoned from, a part of that world comes with them and helps shape the battle ground that the alternate Dissidia takes place in.
However in this world the Gods are stronger, in a sense, but also weaker. Both have a wider range of warriors they can summon, but also less control over bits of the world that are brought by warriors of the opposing side.
It is currently their fifth cycle of conflict, and some of the stage has already been set. Yet as it is still early on not all warriors have defined a side of their own, and have taken up a neutral ground in the conflict. Because of this part of the world may seem imbalance.
Yet now the question remains, which side do you fight for?