Rambtat Forever Soilders

So THETARUNE takes place after all ch7 routes have been completed by the soul/player, and the ending is the same in each one, the roaring happens and everyone dies. Very sad, not that great considering the original ending of the game wasn't supposed to end like that. Even worse is once all three saves are completed, and the game can't finish it's programmed purpose, it starts drawing up a new prophecy, and seeing how the orignal DELTARUNE strongly involved four core people (Kris, Susie, Ralsei and the soul) it named it THETARUNE since it's now drawing three new characters to play the role of those hero's, while the soul is still here because they want to see this through and is needed for obvious reasons

Ramb, Battat and the Blue Rudinn (who I'm just naming "Bludinn" for this) are now put into a bizzaro version of each chapter. Since all copies are monochrome, these "new" dark worlds are all grayscale and turned to stone, although because of the leaking data of the roaring in all other save files, the darkners in those dark worlds still fight, and are incredibly hostile.

Ramb, Battat and Bludinn were all picked by the program because they were the most "important" darkners not in the original prophecy-

(important being measured on how closely related they were to someone in the original prophecy, and since Susie didn't have any big material possession's that could've been darkners and Ralsei didn't know anyone that well who wasn't in the prophecy, Kris has Ramb, and than going out on a limb Kris ties into Dess who had Battat as her dice. Bludinn is here because it just says the players name lol)

-and also are the most unique, being recolors of their species, so their memory in the game files weren't being used up, so they were free to be dragged into this mess

Gaster can't exactly do anything about it, since THETARUNE isn't his creation, it's just something that spawned out of his own program, all he can do is just watch it and hope something good comes out of it