stranger avatar who embodies the fear of running into someone you never want to see again by adopting the visage of said person (idea from @melandrops)
end avatar based off of the washer at the ford/bean-nighe (a passive omen of death rather than an active bringer of it)
flesh avatar who performs gender-affirming surgeries on people with transphobic families (and uses the “disposed of” materials from said surgeries to build a “child” of sorts)
spiral avatar who turns horrors from people’s nightmares into real things
dark avatar who drags people into caves and mutates them to resemble cave-dwelling creatures (colorless skin, no eyes, etc.) until they are barely human anymore
buried avatar who lives at the bottom of the ocean and sabotages submarines/drowns divers
web avatar matchmaker who pulls people into bad relationships
vast avatar who untethers people from gravity and either lets them float endlessly upward or who makes them fall to their death (it depends on their mood)
hunt avatar who turns prey animals into predators and vice versa
extremophile extinction avatar who leads a doomsday cult
corruption avatar who withers/decays/erodes anything they touch
lonely avatar who disappears lone hikers in deep wilderness
bonus: spiral avatar who is a compulsive liar, but whose lies become true for whoever they tell them to