The last chapter of the plot was kind of a hot mess so here's a 5-minute rewrite:
Nyx goes full void and enters the void hivemind, in the process linking with Vocivus and stalling it so the others can act (bonus opportunity to give Vocivus backstory here via mind link if desired)
Ozzy, panicking, tries to figure out what to do. He thinks back on how the paint would flow in response to his spite, and realizes the truth: the paintbrush doesn't inherently turn things gray, it's doing that in response to his hatred. The problem is him.
Ozzy gives the brush to Iridesia to use. Rainbow color flows out and a wave of magic fixes all the gray, causing Voci to freak out and retreat.
The problem is that Nyx is part of the void now, so the color also hurts her, and she tries to retreat as well. Ozzy has to hold her down to keep her from going back into the void (paralleling the situation that got them into this mess)
Iridesia uses their artificer know-how to quickly fix Nyx's shorted out void dampener, which restores her mind (she is still left full void though; this is the first appearance of the color, why would you not want to show it off? Also then it doesn't raise plot holes about if the void corruption is good/bad or why Juni doesn't turn back like Nyx)
Fyora does not resign, but she does feel like Drakara was her fault and decides to elect a ruling council to advise her due to this. The council includes Iridsia and Tavi (as not only are the two friends, but Tavi has been a friend of the faeries for a long time, and having a Neopet on the council would be good for Neopet-Faerie relations).
Ozzy receives the same punishment, but it's handed down by Fyora. She seems like she's going to give him something harsher at first, but Nyx and the new council advocates for him and she cuts it back
Luxinia and Iridesia make out sloppy style