Basically an idea came to me about 2 weeks ago, and i found i have no ability to write it. So i'm putting it as a challenge to any writer that wants to. Plot of it is that a player was pulled into the world, but was sent to the time during the rise of the Demon God. The player is a med-high lvl devil char and finds the Demon God before his rise, basically the player creates the Demon God from a person of the new world. The player becomes the Demon Gods general and is eventually defeated by the 13 heroes, and is sealed within an eternal prison. The prison is bellow the town that Ainz battles the theocracy group the first time, and the battle awakens the player. After that the writer can do whatever they want, but the guidelines are

player is neutral chaotic alignment

player is devil race, and summoner class

player arrives before demon god

player creates demon god

player defeated

ainz accidentally releases player from prison

player did not arrive with big power base like ainz, but one or two npc is accetable

Other then that the writer or writers can go crazy with the story