Aman'Thul was the first Titan to awaken from the long slumber as a world-soul. After his awakening, Aman'Thul started his quest to locate other world-souls and bring other Titans like him out of their slumber. The awakened Titans joined Aman'Thul and they became known as the Pantheon. The Titans of the Pantheon continued searching for other world-souls, bringing order and stability to every world they encountered.
The Pantheon oversaw the creation of innumerable worlds across the Great Dark Beyond and gently guided countless races to greatness. Sargeras was Aman’Thul’s closest advisor and supporter until he turned to evil. Now Aman’Thul looks to his consort, Eonar, for counsel. Though the mysterious High Father is rarely seen, every world feels his presence. As leader of the titans, Aman’Thul is responsible for the creation of all worlds, including Azeroth. All those who revere the titans ultimately pay their respects to the High Father. On Azeroth, explorers have only recently uncovered the titans’ existence, and few aside from the Ironforge dwarves venerate them. Dwarves, being a practical lot, show their respect for the titans by delving ever deeper into their mysteries.
Aman’Thul prefers to keep his distance and pound his foes with magic, casting up to three spells at once (one normal, one quickened, and one hastened). He takes to the air if it seems helpful, hovering above the conflict and raining magical destruction upon his enemies. Against great foes, he uses gate to call Eonar, Aggramar, or Norgannon to his side. He willingly enters melee if necessary, casting quickened spells every chance he can. He uses avatar if he exhausts his spells. 
A tale of Lei Shen extracted from a fragment of Aman'Thul's soul suggests the last members of the Pantheon have been dead for millenia, killed by Sargeras around the time of the forming of the Burning Legion.
In World of Warcraft
This section concerns content exclusive to World of Warcraft.
This section concerns content exclusive to Cataclysm.
The final boss in the dungeon End Time, , revealed to have been , briefly mentions Aman'thul, making it one of the only direct mentions of him in the game:
(Upon defeat) Murozond yells: You know not what you have done. Aman'Thul... What I... have... seen...
The quote reveals Nozdormu's sudden revelation that he was the cause of his own demise; a demise that was shown to him by Aman'Thul at the time he was made Aspect of the Bronze Dragonflight.
This section concerns content exclusive to Legion.
At the end of Antorus The Burning Throne (normal raid), Aman'Thul and the rest of the Pantheon, along with Illidan, trap Sargeras. Before doing so, Aman'Thul says to Sargeras, "Brother! Your crusade...is over!"
- Aman'Thul's lightning powers were likely inspired by Zeus, the Greek god of gods, but his form, personality, and title are cloned with great effectiveness from the Viking chief god, Odin the Allfather.
Aman'Thul has several distinct similarities with the Diamond Warrior Anu from Blizzard's Diablo universe. Both Aman'Thul and Anu are entities of good who were killed seven-headed entities of evil countless millennia ago (Y'Shaarj and Tathamet, respectively)