Not to be confused with the God of Death, Mictlantecuhtli.
Death is both the end of life and a psychopomp. Like most anthropomorphic personifications of death, Death meets with the recently deceased and guides them into their new existence. However, unlike most personifications of death, she also visits people as they are born, according to Destruction. Physically, Death is also opposite to the traditional western culture personification of death (see Grim Reaper). Death is an Endless, and is the sister of Dream.
She has the power to free the soul of a body and send a soul to it's appropriate destination (usually an afterlife or reincarnation). Death often leaves this task to various Death Gods. For Death Gods or demons to claim a soul instead of Death herself, they usually have to have a valid claim on the soul; either a contract or the deceased worshiped the Death God's pantheon. The exact nature of the relationship between Death Gods and Death itself is unknown.
Death apparently is also there at the time of ones birth and can infuse a body with life. She commonly does this at the time of birth or at certain times to give another a second chance (reincarnation). The criteria for the latter is not known.
Omnipresence: Being Death, she is everywhere on Earth at any moment, but not in a form visible to humans, usually.
Omniscience: Death is possibly the most powerful of the Endless having been shown (in a flashback in Brief Lives) to be virtually omniscient and being able to intimidate the Furies, who show no fear of the other Endless, simply by raising her voice. She can see all possible futures and ends for all the beings who fall under her auspice.
'Nigh-Omnipotence': Death is one of the most powerful beings in the DCU, In Madame Xanadu #6, Death was referred to as "she who trumps and defines all of existence".
Shape-shifting: Death could change her appearance and clothing.
Teleportation: She can travel instantly anywhere in the mortal realm that people die and live, and, so long as she shows proper respect, she can easily enter and transit most magical realms, too.
Immortality: Death is ageless and virtually immortal.
Sorcery: Nigh-Omnipotent mastery of magic.
Ancient Rules: Despite her great powers Death, like the rest of the Endless, was bound to a complex set of rules and customs.
One which requires her not to spill the blood of family or she is no longer protected as the personification of Death from other Personifications.
Another rule is that she cannot fall in love with a mortal or the mortal's downfall is assured.