Etri adjusted his coat, fingers ghosting over the dark fabric. “Believe me or not as you will. I only ask that the performers have more care or their lights will go dark.”

Blythe’s eyes fell on the fire at the mention of light. It seemed no longer as bright, like this strange conversation had lasted longer than a few minutes-- or as though Etri walking past had dimmed the flames. Maybe staying out here in the dead of night to talk to a strange boy wasn’t the best idea she’d ever had. Had “lights going dark” meant their props... or something else? “Are you sure that--”

But Etri had vanished as soundlessly as he had appeared. Alone except for the dying crackles of the faltering fire, Blythe shuddered.

-Excerpt from "Spirits by the Campfire"

This week there is a moodboard theme of "transformation," and while I have a few characters who fit this description, the only non-spoiler one is Etri. When he heard this was going to focus on him, he wanted to use his magic to hide so I'd pick someone else... which is exactly why he fits the theme. Etri has shadow magic that essentially turns him into a ghost. He's not dead, not exactly; it's more that he takes on a form that isn't alive in the first place. When he shifts into a shadow, he has no body, only a small amount of presence that allows him to physically interact with the world. Anything he picks up blends into what "Etri" there is and this also becomes intangible until he shifts back. His senses are dulled in this form, muffling sound and clouding sight, but he gains the ability to drift and fit almost anywhere. This helped his previous reverse-thieving career with Sapphire's Saboteurs immensely.

His shadow form doesn't look like much. If it's bright daylight (something he avoids even when human), someone might notice a shadow of an object that doesn't exist or a vague formless shape almost like a faint cloud of smoke. It all depends on just how solid he wants to be and what purpose he's using his shapeshifting for. Most frequently it's the vague cloud because his favorite use of his magic is to vanish in uncomfortable social situations and then move himself up in the highest place he can find. He takes comfort in heights and the quiet of being closer to his beloved stars, and once he's up on a roof, he'll shift himself back into his body. He can also use his magic to cross over to what he calls the "place of shadow," which isn't so much a world of its own as an echo or reflection of the real world. He never stays there long, though. It's lonely even for one who likes solitude as much as he does. The only creatures who live there hardly count as creatures; most are just echos and memories and the few who are more "alive" aren't capable of much communication.

Shifting into a shadow isn't a thing he does openly or talks about often because it has always freaked out his brother and the last thing Etri wants to do is upset Sol. When Adair first meets Etri, the only thing Etri tells him is that he has the opposite of Sol's magic and can snuff out fire and light. Etri's body temperature runs uncannily chilly because of his magic, and this is obvious to the few people he allows to touch him, but he's too afraid of scaring off the people he loves to tell them that there's more to it. The others gradually work out that Etri isn't quite human, although none of them-- Etri included-- know why this is until much later.