One of the first titles that pops into my head is 'Ona, the Last Witch'. It's a lesser-known gem that blends dark fantasy with psychological twists. The protagonist's journey through a cursed world feels like a mix between 'Berserk' and 'Madoka Magica', but with its own eerie charm. I stumbled upon it while deep-diving into occult-themed anime, and the atmospheric storytelling hooked me instantly.
Another series that fits is 'Ona: Guardian of the Lost'. This one leans into adventure-fantasy, with a protagonist who awakens ancient powers to protect her village. The animation style reminds me of early 2000s classics, and the lore expands through light novels too. It’s not super mainstream, but fans of 'Mushishi' or 'Moribito' might appreciate its quiet depth.