In the last mission of the original game, Arkantos, as a demi-god empowered by Zeus, has a final epic duel with Poseidon's Living Statue, and wins!
At the climax of the expansion, Gaia appears in all her glory, swats away enemy forces, and fights Kronus hand-to-hand, then throws him back into Tartarus, saving the world.
The existence of the Tale of the Dragon expansion pack. It's been twelve years since any new content was created, and it looked like we'd never get anything else due to the closure of Ensemble Studios. Cue the gaming company Skybox. Seeing the popularity of Age of Mythology, they teamed up with another company to create some new Chinese DLC that feels very much like the original game.