The unfinished saga of Psychotic Nightmare. It continued after the events of "Alzter's Nightmare", a text-heavy collab where Blueton has to hide from a deranged, evil version of Alzter and calls upon his friends for support. You can find that here:
After Blueton has got all his friends with him, Alzter strikes, breaking through the floor and chasing Blueton and his friends, but before he can catch them Frostburn blocks the way and fights Alzter, who has been taken over by his dark side that has been trapped deep inside him.
They fight for a while until Frostburn can finally rid Dark Alzter from Alzter's body, separating them. Dark Alzter is revealed in his true form, Pitch Dark Alzter. Alzter and Frostburn fight Pitch Dark Alzter until Frostburn gets knocked down by him.
Alzter then retaliates, but not by getting angry. Instead he taps into his true power and turns into Light Alzter. The two fight until Light Alzter finally bests Pitch Dark Alzter, and finally destroys him by throwing him into the sun. After the battle, Blueton and his friends celebrate with Alzter, Frostburn and Nick.
Credit to @ethaneal14, @UltraL14M, @Emily_Sonic_Tails_4, @steamingsheep, @-BluHead-, @shinyzombiepika, @Supererogatory, @CodingProjects, @FoxyForever2005, @-CehLiry-, @Forgivenscrutch, @-Garv-, @joshieman2008 and all the other people who helped along the way.