She revived the worship of Nyarlathotep, uncovered the Shining Trapezohedron, and possessed a magical mirror which functioned similarly to the Trapezohedron.(EXP: "The Mirror of Nitocris", Brian Lumley)
She was said to have invited her enemies to a feast in a temple below the Nile, only to flood it and drown them; and to have been buried alive in the smallest of the three Pyramids of Giza. (HPL: Imprisoned with the Pharaohs, ADJ: "The Queen's Enemies", Lord Dunsany)
Somehow immortal, she survived into the 20th century married to the Pharaoh Khephren, although part of her face had been gnawed by rats. She reigned beneath the earth, with an army of half-human creatures, feeding and worshipping the Sphinx. The locals knew rumours of the truth, and avoided the Third Pyramid at the full moon for fear of her.(HPL: Imprisoned with the Pharaohs) Undead abominations of various origins sometimes attended her feasts. (HPL: The Outsider)
Nitocris' drowning of her enemies is a real legend, albeit apocryphal.