Meticulous categorization of the spectral energy colour would I think be crucial to predicting stuff before it happens. This is more of a reminder for myself.
Zack's comments as compiled here is a goldmine too.
"Not sure about the first question, though I’ll say that there may or may not be a future character who uses Doctopi to their full potential."
"Future character" seems to imply someone who hasn't been introduced yet but as of now the only likely plot-relevant candidate is PJ. Ghosts are also mentioned to be able to do one thing too, and PJ might have died a grisly, sudden death.....though...I'm not sure how that relates to healing
For now, we seem to have a few categories of tangibility of supernnatural beings:
ghosts/spirits, which only differ by their origins,
grudges which I'm assuming are short-power ups(?), though I'm not sure if the only condition for this is being cornered, though both whalefrog and grudgebat demonstrated consuming spectrals and likely therefore their energy before being able to interact with the physical world
poltegeist which are..?? extended grudges?? Spirits/ghosts with strong willpower?
and a weird situation where Spender claims the bat was more than a poltegiest for biting him physically (don't poltegeists already possess the ability to do that?)
"that means the camera is actually recording it, just in a way that’s invisible to normal people, right?
Yes. I have an idea for a chapter using this as a plot device."
This is definitely going to be Suzy trying to blackmail Max by showing him a pic of him and Max observing something in the background that is the key or intro to the spirit behind the chapter or something, and if the foreshadowing is sound, that picture would me of max jumping through the bus, and maybe something on the sideline incriminating Garcia and the Mayview brook!
The threads related to the Mayview mystery are currently- Mayview Maelstrom, as in Spender's room, Spender's shadow tentacle spirit which is presumably the "strongest spirit" that darkrabbit mentioned, PJ's death and mystery for not fading or being absorbed, death of Max's mom, which likely will relate to this somehow (since Maxwell's dad chose to move there to sleuth? In the assupmtion that he's deeper than what his wacky persona currently reveals, which is a given), the purple mountain, and this-
"I think I count four ghosts, and then the hallway of shades from earlier on. Just how many ghosts have died in this school?
Zack: This will be touched on later, but they didn’t all die there, or in Mayview for that matter. It’s just a gathering place."
The cliched prediction, would again, be the maelstrom drawing spirits to the purple mountain which serves as a wave-motion cannon using spectral energy as fodder to...destroy something? Usurp someone? Summon something? Open a portal to somewhere?
We've seen Spender's shades cracking during his fight with Forge, maybe tentacle horrorterror will take advantage of it to release itself from the object later.This was also the thing Spender was likely talking about about his balanced state of mind, with Lucifer and tentacle spirit having a mind battle, and this causing the scales to be tipped in the shadow's favour. Spender seems to be able to use its powers just fine though, making a shadow shield right after its cracking...
So if Shadow's the tool, then Spender is a medium for Lucifer? Or is Lucifer kept in a different tool... We don't really see any manifestation of the light demon in Spender, unless he wasn't a natural blonde or something.