Zagreus (TTs)

Zagreus was the son of Hades and Persephone whom carried the Curse of Tartarus - he was cursed to be the only person capable of entering Tartarus and reporting back on the inmates Status, the Curse was a blessing in a sense that it made Zagreus incredibly powerful and a match for one of the Big Three had he himself owned a Symbol of Power, Zagreus is revealed to be the General of Hades' army and his revealing of Hades favouring the Di Angelo siblings over Zagreus and his siblings causes him to align with his sisters against the Olympians.

Zagreus has done a number of things to rebel against Hades and the Olympian far more apparently than his sisters, Zagreus was the one whom helped Luke steal the Helm of Darkness and the one that helped a majority of the pieces of Kronos come out of Tartarus by creating a shadow-travel link between Tartarus and Kronos' Sarcophagus, Zagreus finally rebels against Hades upon gaining a Symbol of Power for himself and having the amnesiac Iapetus take over for Cerberus as he took his three-headed pet as his steed.

Zagreus apparently, like most minor Gods, is a perfect translation between Greek and Roman myths alongside: Apollo, Aphrodite/Venus (her nature doesn't even minorly change) Macaria, Melinoe, the Titans (their nature has only minor changes) and many minor Gods.

Trivia

 * Like all of Hades' Godly children, there is confliction on if Hades is truly Zagreus' father, sometimes it is believed to Zeus.