Shadow watcher

(it doesn't actually have a gender since it's just... A shadow so uh yeah) You are something or... Anything idk be whoever Shadow watcher: a shadow but it's actually sentient and is pretty tall... It has glowing white eyes and holds a lantern. If it's in the light it'd very visible but if it's in the dark nobody can see it...it is a very powerful being but it does regularly kill people for fun. It can go into you're shadow and surprise attack you or when it's dark in can change it's form to something really fast and kill you idk good luck...