Elemental hierarchy

It is possible that the elementals of Azeroth have formed a hierarchy within their respective region of the Elemental Plane, explaining their ranks and titles. Powerful elemental beings have titles such as Baron, Lord, and Duke. The most powerful ones are known as elemental princes, and they are usually the offspring of the Elemental Lords.

Lesser elementals are low-ranking among the elemental hierarchy.

Speculative hierarchy
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Deepholm

 * - Earth Lord: Therazane
 * - Earth Princess: Theradras†
 * - Stone Lords: Boden, Diamant, Felsen, Gorsik, Kor, Terrath, Ruberick and Ma'haat
 * - Deepholm inhabitants and creatures: Earth revenant, death revenant, earth elemental, earthen and stone troggs, geode, gyreworm, shale spider and stone dragons

Firelands
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 * - Firelord: Smolderon (previously Ragnaros†)
 * - Majordomo of the Firelands: Fandral Staghelm†, Executus†
 * - Firelands inhabitants and creatures: Fire revenant, molten giant, fire hawk, flamewaker, fire elemental, lava elemental and druids of the Flame, core hound, lava worm, phoenix, fire spider, hell hound and firekin

Skywall

 * - Windlord: Thunderaan (previously Al'akir†)
 * - Air Prince: Sarsarun†
 * - Conclave of Wind: Anshal†, Rohash†, Siamat†, and Nezir†
 * - Skywall inhabitants and creatures: Djinn, arcane wraith, lightning revenant and air elemental, storm dragon, spark

Abyssal Maw

 * - Water Lord: Neptulon
 * - Abyssal Maw inhabitants: Water revenant, sea revenant, ice elemental and water elemental

Hierarchy in the RPG
At the lowest level are elemental sprites, tiny creatures that exist as a living aspect akin to their element. Mephits and lesser elementals are next in power, followed by others in order of strength. Other types of elemental kin, such as revenants, djinni, xorn, phoenixes and salamanders, can also be found in various levels of strength. At the top reside the elemental princes: unique, named beings with special abilities and great powers, often exceeding those of the elder elementals.

Unless indicated otherwise, the following is a list of the known elemental hierarchy from the Shadows & Light RPG source book. They are listed from the highest rank to the lowest along with their size or status.

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Earth

 * Highest: Therazane (elder)
 * High: Elder xorn (huge),
 * Medium: Average xorn (medium), Death revenant (large)
 * Low: Minor xorn (small)
 * Lowest: Stone sprite, Earth mephit

Fire

 * Highest: Ragnaros (elder)
 * High: Efreeti (huge), Phoenix (greater)
 * Medium: Fire revenant (medium), Salamander (large)
 * Low: Azer (small), Magmin (small)
 * Lowest: Flame sprite, Fire mephit

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Air

 * Highest: Al'akir (elder)
 * High: Djinni noble (huge)
 * Medium: Belker (medium)
 * Low: Djinni (small), Frost revenant (small), Lightning revenant (small)
 * Lowest: Spark sprite, Air mephit

Water

 * Highest: Neptulon (elder)
 * High: Elder tojanida (huge)
 * Medium: Adult tojanida (medium)
 * Low: Juvenile tojanida (small), Ice revenant (small)
 * Lowest: Frost sprite, Water mephit