The sword could only be used by someone who was chosen as worthy enough by the sword. Once the desired wielder attuned the sword, a dramatic physical transformation occurred. The wielder became angelic, being given great beauty and a heart filled with good. The wielder's alignment was changed to lawful good. These changes could not be reversed by either interference from a celestial being or magic.
A large pair of angelic wings grew from the wielder's back. They allowed the wielder to both fly and hover. The wielder's eye were changed as well, glowing with a faint silver light. This gave the wielder increased vision, allowing one to see in both magical and natural darkness and to detect illusions, polymorphed creatures, shapechangers, and invisible creatures or objects. The wielder was also capable of glancing into the Ethereal plane.
As well as physical changes, the sword bestowed other powers. The wielder gained full knowledge of the celestial language, an increase in charisma and wisdom, and a resistance to both necrotic and radiant damage.
The sword illuminated an area with a 10 ft (3 m) radius in a bright, holy light. This light was a bane for fiendish creatures, who found the light painful. The wielder was able to control the brightness, dimming it or increasing its luminosity to cover an area with a radius of 15 ft (4.6 m). The sword delivered radiant damage to all evil creatures, who became blinded when struck, in addition to normal physical damage.
The sword was sentient, capable of communicating with the wielder by the transmission of emotion. It had the ability to hear sounds and speech and to see in the normal spectrum up to 30 ft (9.1 m) away.
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