The One King

The One King is the final villain of Suikoden Tierkreis. His goal is to merge all worlds within the Infinity into his own worlds where the inhabitants' best day in their lives repeat forever, thus creating a future that is always predetermined.
It is unknown when the One King appeared, but he could be assumed to have first shown up at least 8 decades before the start of the game. As said by him during the game's main ending, the One King is created when the Tenkai Star of a world is defeated by The One King, thus he has no future or past, only conflict.
The Order of the One True Way in many worlds worshipped the One King and awaited his arrival. He would arrive when 12 worlds were "fused" with that world, which usually meant a century to wait. However, many leaders of the Order learned of a ritual that would allow the One King to arrive much quicker. Because of this, the worlds within the Infinity began to diminish quickly, giving the One King an incredible amount of power.