do you have any headcanons about non-human ghosts/ghosts that originate from the ghost zone? like behemoth and the ectopusses and other creatures like that?
I do, in extensive detail! I like to think that creature-ghosts were actually once a part of the human world, physical manifestations of natural forces and other living things or magical myths and legends that gained some kind of form.
But as time went on and people developed the land or stopped believing in them, their power weakened, so they moved to the Ghost Zone—basically just another universe where physical dimensions don't exist and everything exists as energy—to keep from dying out altogether. Some return to the human world every now and then because, hey, home is home, but they don't stay very long.
I applied this concept to Frostbite's people in Chapter 11 "Syndis" of Familiar:
[Vlad] scoffed. “It’s no wonder you simple-minded savages died out.” [...] Danny’s head swiveled back and forth. “Wait, what’s he talking about? Who died? And what’s a yetnar?” Invisible weight settled on Frostbite’s shoulders. “That is the name of my people.” He lowered his heavy frame onto one of the benches, thick tail curling on the floor. “We had many names once. Thurs, risi, jötunn. We were forces of nature, earth spirits, guardians of the hidden places. We kept to ourselves, caring for the earth, weaving poems and magic.” “Whoa, hang on a sec. You mean you’re from my world?” “The Norwegians called them trolls,” Vlad muttered, waddling over to an adjacent bench and plopping down. “The Tibetans, yeti. Nearly every culture on earth has its own iteration. You can tell they’re not normal ghosts by the color of their spectral radiance.” Danny blinked. Vlad was right. Instead of the typical white glow that human entities emitted, Frostbite and Eisvin glowed blue. Danny felt painfully stupid for not noticing it sooner. “This is true,” Frostbite admitted. “We are not normal ghosts, for we were never living flesh.” “So how does that work?” Danny slid into the vacant spot beside him. “How can something not living be killed off?” “Our powers came from the earth, young one. From all living things. As time went on and humans progressed, the forests shrank. Animals retreated or disappeared altogether. Science and technology prevailed. Instead of living in harmony with nature, men and their machines soon dominated everything. We became few and weak. The magic that sustained us dwindled as centuries passed, and eventually we had no choice but to come here, the realm of ghosts, or face our own extinction.” He tilted his head back to stare up into the mountain’s dark crown. “It’s not much of an existence, but it’s better than fading away.”
So I headcanon that the ectopusses were probably some kind of sea monster, Behemoth was the physical embodiment of an ancient curse (protecting the Skeleton Key), and beings like Vortex, Undergrowth, Nocturne et al were probably ancient proto-deities of the weather and agriculture and sleep/dreams.
