In The Sandman universe, Death is the most powerful Endless. The power levels of the siblings are largely related to their age. The older an Endless is, the more powerful they are. However, despite being the second-oldest
Destiny, the eldest of the Endless, is one of the most powerful and influential of his siblings. As the ultimate observer, Destiny is the personification of fate and is generally all-knowing. Destiny is blind and largely unconcerned with action, preferring instead to observe.
There's a 'vibe' in the series of the endless having a power rank roughly in line with their ages (oldest to youngest), which fits well with dream's speech. Of the six mentioned so far the age order is Destiny > Death > Dream > Desire > Despair > Delirium.
Most likely Lucifer. Lucifer is without a doubt stronger than all of the Endless and would beat any of them in a one on one fight. Lucifer is stronger than Morpheus, by far. And is considered by him to be the most powerful being there is, right after God.
Dream (aka, Morpheus) is one of seven immortal beings known as the Endless, who are even more powerful than the gods.
More than a mere personification of abstract concepts, each Endless is the idea itself, making them immune to death or destruction. While even god can be slain, a fallen Endless is merely replaced by another version of itself because the universe cannot function without these concepts.
Destiny – The eldest of the Endless, he is chained to a large tome known as the Cosmic Log, which contains the sum of all existence in its pages. He is much like his book, possessed of unshakable certainty and equanimity but lacking any ability to change or be spontaneous.
7. Delirium. The least powerful of the Endless is poor Delirium, who was once Delight.
Delirium, the youngest, once known as Delight. No one knows why she changed, except perhaps for herself. Her hair changes on a whim, ranging from long to shaven, or both, from red to orange to multicolored.
The seven siblings are Dream, Despair, Desire, Death, Destruction, Delirium, and Destiny, and "The Sandman" comics eventually show them all in some manner,...
Death is the second eldest of the Endless, a family of beings that personify natural forces.
Father Time is the personification of Time and rules over his domain. Time is the father to the Endless and with his partner Night, made all of Creation possible. However, in present times, Time and Night are separated and estranged from their families.
The Endless are said to be older than the fairy-folk, gods, and other supernatural beings. Their exact ages in years are unknown, but they are known to have existed long before life on Earth; Destruction says that he has performed his duties—not counting the previous three centuries—for 10 billion years.
The Endless are a family of beings who appear in American comic books published by DC Comics. The members of the family include Death, Delirium, Desire, Despair, Destiny, Destruction, and Dream.
While there are other siblings that have been mentioned and not featured in the series, The Prodigal's absence raises more eyebrows than rest. During Morpheus' pensive walk with sister Death (Kirby Howell-Baptiste) the two briefly discuss The Prodigal's whereabouts, with Death confessing that he was still missing.
Dream/The Sandman
The title character of The Sandman has more names and titles than he does friends, but he most typically goes by Dream of the Endless, or Morpheus. The third oldest of the Endless, Dream came into being when the first sentient life began to think of things beyond simple survival.
The Endless: Destruction Is the Missing Prodigal
The Endless, in order of appearance in the universe, are Destiny, Death, Dream, Destruction, twins Desire and Despair, and Delirium, who was once known as Delight.
Death is the second oldest of the Endless and the elder sister of Dream. To the ancient Greeks, she was known as Teleute.
In The Sandman, God is referred as “The Presence,” and his existence can be sensed by anyone and everyone. Also, whether God is or is not present himself, his power and domain surround others. The scene of Moses and the burning bush is similar to the portrayal of Hell present in Sandman: Preludes and Nocturnes.
Powers. Personification of Dreams: As one of the seven Endless, inconceivably powerful beings, Dream is both the lord and personification of all dreams and reality. He possesses absolute control over sleep, dreams, nightmares, and even insomnia.
The personification of Death (Kirby Howell-Baptise) is the elder sister of Dream as well as his go-to confidante.
That means Destiny is the most powerful and Delirium the weakest. I however think this order of age and power makes more sense: Destiny, Dream, Destruction, Death, Delirium, Desire, then lastly Despair.
The Endless are a somewhat dysfunctional family of seven siblings who each represent an aspect of the universe: Dream, Death, Destiny, Despair, Desire, Delirium and Destruction.
By the time he returns the Kindly Ones are in the heart of the Dreaming. Morpheus summons his sister Death, who kills him.
The witch Thessalay has said that Death, alone of the Endless, is not bound by rules. Given this, it's entirely possible that her incarnations cannot die. That said, IF she can die, I expect the next incarnation would be immediately selected. The next incarnation would almost certainly ferry her.