Originally Delroy Garrett, Jr was an Olympic medalist with a bright future until it was discovered that he was using steroids. As a result he was banned from competing and his life was in ruins. As a result he joined the Triune Understanding to restore his shattered faith and went under the tutelage of
who was its leader. Tremont then bonded Delroy with the stolen powers of 3-D man and he became Triathlon, the spokesperson for the Triune. However, he was unaware of the source of his powers and believed that it was the Triune's teachings that had unlocked his full potential.
Mayor Story Arcs
After this came Triathlon's first meeting with the Avengers and he aided them in their battle against Moses Magnum which ended in the villains defeat. He then helped them against Lord Templar and Pagan at the dedication of the new headquarters of the Triune Understanding. However, the villains escaped and Jonathan Tremont blamed the Avengers for the destruction of their new building and used this incident as the first part of his smear campaign against them, accusing them of being racist and not having sympathy towards other people's beliefs and religions.
Tremont then hired Taskmaster to destroy another Triune building once again blaming the Avengers, however, this time he publically forgave them and they had to go along with it so they did not get any more bad publicity. This was followed by a terrorist attack on the Avengers building that was once again thwarted with the aid of Triathlon. It was at this point that then liaison Duane Freeman suggested that Triathlon become a member of the Avengers in order to stem the flow of the bad publicity. Despite their being some animosity towards this decision, Delroy was eventually inducted and their announcement was made public. Even though proved himself to be a useful addition to the team, the manner of his arrival still annoyed many of the current members and as a result arguments often broke out. However, with Warbird's assistance he discovered that the rest of the team were good people and the arguments ceased.
During Kang's war on earth, a being known as the Triple Evil entered the solar system and Tremont stated that this was the entity that he created the Triune Understand to defeat. This caused an un-easy alliance between Tremont and the Avengers in which they went to space to confront this being. However, during this battle Tremont's true objective became clear: he wanted to use the power of Triple Evil for himself and that he had used the stolen power of 3-D man to resurrect his two dead brothers as the villains the Avengers had fought previously - Lord Templar and Pagan. Tremont then killed his brothers and absorbed their power and the final element of the triangle power which was the Triple Evil. However, he lost control of the power he had stolen and it was up to Triathlon to ultimately channel this power and defeat Tremont once and for all. When the Avengers returned to earth they then defeated Kang and his army but the team was the re-organized under the United Nations and several members left including Delroy.
His most recent appearance was at Captain America's side during Civil War as part of his Secret Avengers taking a stand against the Registration Act. However, after the battle had reached its conclusion and Tony Stark came out the victory he offered full pardon for all the heroes on the opposing side. Delroy then became a trainer in the Initiative and the new 3-D Man.
Avengers: The Initiative
Having graduated from the Initiative, Delroy would become a member of "The Point Men". He would be stationed at Hawaii. Having gained the original 3-D man's goggles that would allow him to see Skrulls in his presence. While meeting his fellow teammates, Delroy realizes that one of them is a Skrull. Thanks to the Devil Slayer, Delroy uses his magical sword and slays the Skrull. The Devil Slayer then transports Delroy to Camp Hammond by use of his magical cloak. The Initiative member Crusader fearing that Delroy would let the others know that he is Skrull, talks Delroy into using a Quinjet to get some help, because Camp Hammond was infested with Skrulls. While airborne the Quinjet became effected by a virus that shut all the systems down, and he crashes in New Mexico. That is where he would meet the Skrull Kill Krew. Delroy would join them in the hunt for Skrulls one Intiative team at the time, during the Secret Invasion saga. He and Ryder are all that are left from the Skrull Kill Krew and continue to travel and hunt Skrulls that are still left on earth.
Agents of Atlas
Following the end of the hunt for Skrulls, Delroy and Ryder parted ways. Delroy remade his costume to reflect the original 3-D Man's costume. He soon found the original 3-D Man and his wife killed by a mysterious group before being hunted himself. The Atlas Foundation met up with Delroy and explained that the group was part of a hidden city that was connected to the original 3-D Man's origins. The Atlas Foundation eventually found their way to Echo City and discovered they were the race that were created by the original Triune, which forged the 3-D Man and Triple Evil's powers original. The Atlas Foundation eventually brought down Echo City and sealed it off from society to keep them from causing the world to plunge into extinction. Following the end of the event, Delroy joined the Atlas Foundation.
Triathlon has superhuman strength, durability, speed, agility, reflexes, and jumping at levels exactly three times that of the perfect human athlete.
After taking the mantle of 3-D Man Delroy was given a pair of Skrull-Detecting goggles from the original 3-D Man.
The goggles allow him to immediately spot any skrull.