Tyndarius is the leader and warlord of the Firestorm Onslaught, and the Fire General of the Queen of Monsters. He is a pyromancer who rose through the ranks after joining the Calderan Guard. Kyron knew he was special the moment he saw him do so, but he couldn't foresee the fact that he attacked his own home in the Firestorm Caldera.
One day, Tyndarius was visited by the Queen of Monsters in his dreams, who offered him a contract that would give him absolute power if he signed it. Not long afterward, he sent a division of the Firestorm Onslaught soldiers to attack Pyrewatch Peak as a distraction for another division to use to attack Feverfew Falls. The soldiers kidnapped several residents of the Caldera within the temple and carried them off to the Phoenixrise Gates, after which the heroes followed.
After defeating Cinderclaw in the Fyreborn Caverns, the heroes were able to confront Tyndarius himself, unaware that he had already sacrificed a few of the people to free the first of the Chaos Titans, the Fire Titan Phedra. Tyndarius offered to have the heroes trade their freedom for that of the remaining survivors and face the Firestorm Forge, and they agreed. The heroes fought their way through the Firestorm Forge, ultimately earning the right to face him in battle. Tyndarius defeated the heroes and revealed that the fate of the unworthy is to serve the Risen One for the glory of the Queen.
Later, General Phyrz reported to him that the heroes had escaped and that the priests of Embersea had begun chanting and communicating with Neso, the Lady of the Waters, to enhance the Aqua Pyrrus potion to help douse his flames. Enraged, Tyndarius assumed a secondary form and vowed to break the necks of the heroes and build a bonfire with their bones. Not long after the Phedra's defeat, the heroes entered their second showdown with the Firestorm Warlord himself, and with the aid of the enhanced Aqua Pyrrus potion given to them by Pyralis, they were able to defeat him. The Queen of Monsters rescued him, and, having learned of what happened at the Ring of Fire Islands, vowed to make their people pay for what they did and the Water Plane boil for the insult they had given her.
Tyndarius would later return when Malgor offered him a chance for godhood by offering him service to him and an opportunity to attack the Plane of Fire and claim Fiamme's power as his own; an offer which he accepted. Both went on to confront and attack Fiamme, with Malgor draining her powers out of her and leaving Tyndarius to absorb it and become an Avatar of Fire himself. Before Malgor could murder Fiamme, though, she awakened Galanoth, who, along with the heroes, had just arrived at her throne room to confront them, as the Champion of Fire, and he blasted Malgor with his flames and carried her out alongside the heroes.
- His name is a corruption of the name "Tyndareus". Tyndareus was a king who ruled Sparta in ancient times.
- His animal motifs for his armor and clothing are the tiger and the phoenix.
- He seems to share some similarities to Chaos Lord Escherion from the "13 Lords of Chaos" storyline. Both are among some of the first of a type of major villain in their respective storylines (Escherion was the first Lord of Chaos, and Tyndarius was the first to be revealed as one of the Queen's Generals), and they both use a cylindrical-shaped weapon (the Chaos Staff of Inversion for Escherion, and a fiery spear for Tyndarius). They also both wear corinthian helmets, and they also introduced the heroes to a special type of monster (Chaos Beasts for the Chaos Lords, and Chaos Titans for the Queen's Generals). In the end, they both transformed as well, the only difference being that Escherion ended up turning himself into a frog when he tried to invert the heroes, leaving himself harmless in the end. Tyndarius, on the other hand, assumed a secondary form and used it for his second fight against the heroes. Also, they are both a different type of mage (Escherion is a battleMage, and Tyndarius is a pyromancer), and they both had jokes and puns directed towards them by the heroes as well (they used frog puns after Escherion turned himself into a frog, and they used fire jokes in battle with Tyndarius).
- He also seems to share some similarities to Maximillian Lionfang. Their armors are based on a type of cat (lions for Lionfang, and tigers for Tyndarius), and their faction name also has the word "Onslaught" in it (the Golden Onslaught/Chaonslaught for Lionfang, and the Firestorm Onslaught for Tyndarius).