Beginnings of Her Creation
In the picture to the left, if enlarged, you will be able to read Neil Gaiman's (creator of The Endless) description of how he came up with her and what she means, etc. You can find this excerpt in "A Death Gallery" #1 where many pictures of her are also featured.
Younger sister of Destiny, older sister to Dream, Destruction, Desire, Despair and Delirium. It is said that everything living thing encounters death twice in their lifetime. Once when they are born, though no one remembers that meeting with her, and once when they die. Death does not guide the soul of the dead into any particular afterlife, she is merely a gateway into what lies beyond. On page she usually appears as a young woman, stylishly dressed wearing a silver ankh, with pale skin, and an eye of Horus tattoo around her eye. Though like the rest of the Endless, she can appear however she wants or needs. When the universe was young Death was more somber, but she has come to love her job and develop her own quirky upbeat personality beyond what the fear living beings have of her. It is known that she keeps two goldfish and has a floppy hat collection. She is Dream's closest friend and confidant, able to shake him out of self-absorption when necessary. She does not seem to have much of relationship with either her elder brother Destiny, nor her younger siblings. Twice Death has agreed not to take people (on panel). In one instance it was her nephew, Orpheus so that he could descend into Hades and bring back his love Eurydice. After being torn apart by the
Bacchanae, Orpheus survived for thousand of years as just a head until released (killed) by his father Dream. The second time in Medieval England, after listening to a man claim that Death was "a mug's game", she agreed not to take Robert Gadling while Dream agreed to meet him every hundred years for a drink, just to see how long he would want to live. After Dream (Morpheus) died, she met with Gadling herself and offered to take him, but he refused.
One day in every century, Death lives a day in mortal form, sometimes human, sometimes not, to better understand the creatures over which she has dominion. "I'm not merciful or blessed. I'm just me. I've got a job to do and I do it....When the first living thing existed, I was there. Waiting. When the last living thing dies, my job will be finished. I'll put the chairs on the tables, turn out the lights and lock the universe behind me when I leave."
Death - despite her job description - has always been the perkiest of the Endless. While Destiny - the eldest of them - is very cold and detached, Death is warm and caring and she has taken the role of the mature maternal sister among the siblings. She can be frequently seen throughout the The Sandman series serving as Dream's confidante, giving advice and pointing out his faults or getting angry at the twins Despair and Desire for their "games", which often intervenes with the other Endless' affairs. She is closer to Dream than any other member of the Endless, and he sought her advice on several occasions. She also has shown that her job takes a backseat when it comes to her family, unlike Dream and Destiny, both of whom seem to take their job very seriously.
Powers and Abilities
In The Books of Magic #3 (the second series), as Tim Hunter lies in a field of plant life, his thoughts slowly drifting away and Tamlin trying to care for him, he says something that may reveal more of Death's powers than are ever explained when he says. "I know what holds the world together, now. Except it's not a what. It's not even an it, really. She's pretty... She's so pretty..."
Death was able to banish the Furies from the Dreaming with ease, and was powerful enough to scare Desire, who was one of the Endless herself. She is also capable of being in innumerable places at the same time. It was stated by Delirium that only Death would survive the end of the universe.
Gift of Death
She has the power to free the soul of a body and send a soul to his 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 worshipped the Death God's pantheon. The exact nature of the relationship between Death Gods and Death itself is unknown.
Gift of Life
Death is apparently also there at the time of one's 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) or to create new life (Eblis O'Shaughnessy). It is also known that at certain times she has chosen to stay her hand indefinitely, as in the case of Hob Gadling and the Dead Boy Detectives (ghosts).
Omnipresence: Being Death, she is everywhere on Earth at any moment, but not in a form visible to humans, usually, thought she can choose to be seen if she wishes.
Near-Omniscience: She can see all possible futures and ends for all the beings who fall under her auspices. Due to her nature she knows whenever an entity is born and whenever a person, animal or plant is about die and appears whenever that is the case.
Nigh-omnipotence: Death is one of the most powerful beings in the DCU, although even she is inferior to beings like Lucifer Morningstar. In Madame Xanadu #6, Death was referred to as "she who trumps and defines all of existence". 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.
Shapeshifting: Death could change her appearance and clothing at will. Thought like her brother, how she appears may depend on the eyes of those who see her.
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.
Immortal: Death is ageless and immortal, predestined to be the only being that will survive this universe.
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 is that there are certain beings who are beyond her jurisdiction and cannot be taken by her, but only Lucifer Morningstar has been revealed as one of these.
All of the Endless are however barred from entering a crypt within the Necropolis Litharge where their funeral garbs are kept. Why they are barred is unknown, but Despair makes a point of 'even our sister cannot enter' meaning Death since she was talking to Delirium.
Known Relatives: Delirium (sister), Desire (brother/sister), Despair I (sister, deceased), Despair II (sister), Destiny (brother), Destruction (brother), Dream I (Morpheus, brother, deceased), Dream II (Daniel, brother), Orpheus (nephew, deceased), Miranda Walker (niece), Rose Walker (grandniece).