Bioroid Squad 5 was a squad of Tirolian mecha that were stationed at the capital of Tiresia. Operating various models of Bioroids, they were stationed at the Royal Hall pyramid. After the Robotech Masters departed Tirol, the planet came under siege from the forces of the Invid Regent who were seeking their stolen Flower of Life. Their assault managed to overpower the defense grid around the city and left Tiresia in ruin.
At the height of the battle, squad 5 was deployed into battle against the Invid mecha who suffered casualties but were overwhelmed by Armored Scouts. Ultimately, the group was defeated when Invid Shocktrooper enforces were deployed onto the ground who made short work of the weakened squad. However, at least one of the pilots was able to escape their mecha before it was destroyed.