Immortality

Immortality is the power of having the potential to live forever if unharmed. However, immortality doesn't imply invulnerability to physical and/or spiritual attacks.

Entities possessing this power

 * Angels: As very powerful celestial beings created by God and Goddess seconds after the Big Bang, angels are immortal, they are as old as the universe. Angels have an eternal lifespan, and they will live forever and will live for all eternity without ever aging or decaying.
 * Demons: Being malevolent, supernatural entities that originate from Hell, though most are billions of years younger than Angels- except for a select few like some members of the Council of Hell, demons are ancient supernatural beings, and were created many eons ago. Demons are immortal, and can absolutely live forever.
 * Gods: Gods are eternal.
 * Cain: Amenadiel was sent by God to curse Cain with the mark of Cain. This mark cursed him to be immortal.

Vulnerabilities
Demon Daggers: These blades have the ability to harm Angels and kill Demons on Earth.

Chloe Decker: Chloe causes Lucifer to be vulnerable so when she is around Lucifer, he becomes mortal.

Flaming Sword: This sword has the ability to kill Angels, Demons, and Gods. When killed with this sword they no longer exist, not even in Heaven or Hell.