The male individual known as Grodin Tierce's clone was a Human from the Legends continuity. This clone of the Royal Guardsman Grodin Tierce, in conjunction with the con artist Flim and Moff Disra, endeavored to rescue the Imperial Remnant from impending defeat at the hands of the New Republic.
Following Palpatine's death, Grodin Tierce served as a stormtrooper officer under Grand Admiral Thrawn aboard the Star Destroyer called Chimaera. Thrawn, impressed by Tierce's combat skills and physical attributes, selected him as the template for a novel type of clone two months prior to the Battle of Bilbringi in 9 ABY. Rather than simply replicating a skilled warrior or sleeper agent, Thrawn utilized technology discovered in Mount Tantiss to transfer his own strategic brilliance into the flash learning matrix. While his intention was to create a formidable group of warlords combining stormtrooper strength with his own tactical acumen, the Tierce clone proved to be merely a "tactically brilliant stormtrooper", rather than a genuine leader. The project was abandoned when the original Tierce perished during Thrawn's campaign on Generis; the clone then assumed the identity of his progenitor, marking the beginning of mental instability. The cloned Tierce personally apprehended and killed the escaping Noghri Rukh after he fatally stabbed Thrawn.
By 19 ABY, Tierce had risen to the rank of Major and became an aide-de-camp to Moff Vilim Disra, who remained unaware of his clone status. After Disra revealed his knowledge of Tierce's past as a Royal Guard, he entered into an alliance with him and Flim, who was posing as the deceased Grand Admiral. Tierce exploited Disra as a pawn and a source of resources to implement a Thrawn-inspired strategy aimed at preventing Supreme Commander Gilad Pellaeon and the Imperial Remnant from surrendering to the New Republic. This soldier hybrid covertly distributed altered versions of the Caamas Document to manipulate the latter, while Flim and Disra's forces dealt with the former. He propagated rumors of Thrawn's return, thereby sowing discord within the New Republic.
Ultimately, Tierce's own madness led to his downfall. Gilad Pellaeon, who had no knowledge of the scheme, managed to uncover the truth about the clone's origins, expose Flim as an impostor, and negotiate peace talks with the New Republic. He revealed to Tierce that he was deemed a failure, leading to the project's cancellation due to Tierce's undesirable qualities. Tierce's clone ultimately met his end at the hands of Shada D'ukal, the bodyguard of Talon Karrde, when he attempted to assassinate Pellaeon.