The Breen

This species is a powerful race located on Breen in the Alpha Quadrant. Mysteriously they are one of the most underestimated races. The Klingons were the first to discover this race. They sent a fleet to invade their space, however the fleet was never heard from again.

Thy ' lek Shran

This Andorian commander was in the Imperial Guard in the 2150s. Despite his xenophobic background he became Archers alley, thus Starfleets and strengthened ties between Earth and Andoria. In 2142 he was promoted to commander of the warship Kumari.  He led a team which invaded a Vulcan Sanctuary called P'Jem in search of a listening post illegally monitoring Andorian space. They raided the Temple three times until they found it. Shran imprisoned T'Pol, Tucker and Archer for their belief of collaborating with the Vulcans.

Grathon Tolar

Grathon was a skilled holographic forger. In 2347, he was awaiting execution in a Klingon prison, but Sisko got him pardoned in exchange for a holoprogram. The program was to be of a high level Dominion meeting in which a supposed plan for the invasion of Romulus. When he finished, however it did not fool the Romulan Senators Vreenek. He was about to take the evidence back when his shuttle exploded from a bomb Gerek implanted.