Immortal

An immortal is a being who possesses immortality. Immortality is a state of changelessness of varying degrees which ranges from resistance to normal causes of death to complete immunity.

Official Warcraft Encyclopedia
Verbatim from the Warcraft Encyclopedia:


 * Many immortal and near-immortal creature' exist in Warcraft. A number of these creatures are fundamentally incorporeal beings, but others lead a primarily physical existence.


 * The Nature of Immortality


 * Immortals in Warcraft are generally resistant to sickness and injury, but immortality does not confer invulnerability. Immortal beings can still be wounded and even killed. Indeed, many immortals have perished over the course of recorded history, particularly during the War of the Ancients. The death of an immortal is just as real as any mortal death and, barring a few extraordinary cases, just as permanent.


 * What, then, does the term immortality mean in Warcraft? Immortal creatures essentially stop aging when they reach adulthood, and thus, they cannot die merely from old age. In addition, they tend to be more powerful than most mortal creatures, although this tendency does not always hold true. Even godhood itself is no guarantee of superior might. Consider the titans' defeat of the Old Gods. The titans are not gods, but their vast power allowed them to imprison the Old Gods far below the surface of Azeroth.


 * Furthermore, immortality need not be a lasting state of affairs. The night elves, for example, were immortal for thousands of years, but sacrificed their immortality during the Third War. Today they are a mortal race, and they are accordingly classified as such, rather than listed herein.


 * There are also quite a few races and individuals who have attained immortality after leading a mortal existence. Most demons in the Burning Legion were once mortal creatures.


 * Last but not least, there are creatures that can be considered nearly immortal. Technically these beings are mortal, but for one reason or other, they have a lifespan that greatly exceeds several millennia. Indeed, these mortal creatures might even be considered effectively immortal due to some external factor, as with Ysera's consorts, who almost never emerge from the Emerald Dream.

Night elf immortality
Night elf lore suggests they were once immortal, but sacrificed this gift during their conflict with the demons of the Burning Legion. However, little lore exists to explain how they first gained immortality. Some tales hint that the night elves achieved some form of link between their spirits and the eternal world, but the details are not clear. The early history of the night elves suggests their immortality was indirectly granted to them by the Titans via the Well of Eternity. The early night elves gathered around the Well and its energies infused them as they built their civilization. With the destruction of the Well, their resistance to death was lost also.

Other stories credit Nozdormu, the Timeless Dragon Aspect of the bronze dragonflight who blessed the first World Tree, Nordrassil, with the gift. The connection between Nordrassil and immortality relies on the hint from the early myths that the Well of Eternity by itself only offered partial immortality while near it, while Nozdormu's blessing permeated any elves who where born among the first world tree's branches. The reasoning goes that the later world tree, Teldrassil lacked this blessing and that is why it would not allow the elves to regain their immortality from it. However, Nordrassil was also grown from the waters of the Well of Eternity and Teldrassil was not. Also, the promise of immortality associated with Teldrassil comes primarily from Fandral Staghelm and not from any divine beings. Nozdormu, perhaps tellingly, withheld his blessing due to Fandral's actions during the war against the qiraji and so Teldrassil lacked another property of Nordrassil. Thus, Fandral's promise has yet to come true.

Speculation on immortals

 * Certain Draenei have lived over more than 25000 years like Velen and might be immortal.
 * They do age however as Velen is clearly older than most Draenei.


 * Creatures like the Naaru, Titans, Old Gods seem to have existed since the dawn of creation and are at least as old as Azeroth.


 * Demons and creatures empowered with demon magic seem to live much longer lives because of their sustainement by fel magic.


 * Mechagnomes are said to be immortal. This counts for both mechagnomes who were not originally flesh gnomes and flesh gnomes who have been turned into mechagnomes, thus being freed from the Curse of the Flesh.