Tunzos was a 23rd century Klingon man, a captain serving in the Klingon Defense Force. He was an intelligent, determined and thoughtful commander, unless provoked.
Biography
By the 2270s, he had assumed command of the K't'inga-class IKS Rakor.
In 2273, Tunzos was ordered to capture or execute at all costs two Klingon dissidents, Chetar and Morg, criminals who had spoken out against the government. The fugitives were traveling aboard an old Vegan Tripper-class commercial flyer near the planet Telos. When IKS Rakor caught up with their ship, it was in orbit of Telos next to the recently refit USS Enterprise.
Tunzos hailed the Federation starship only to learn that the criminals had been granted political asylum. He was calm until James T. Kirk suggested that Tunzos follow diplomatic methods to get the criminals back, when he fired a torpedo at the Enterprise. Kirk fired back with a warning shot. Tunzos then brought his ship within fifty meters of the Enterprise to stare Kirk down. He gave Kirk an hour to comply, undisturbed by the possibility that weapons fire from such close range would destroy both ships.
Chetar and Morg chose not to accept sanctuary within the Federation. They fled in their spacecraft while the Enterprise blocked their line of sight to the Rakor. Kirk then fooled Tunzos by launching a pair of travel pods. Tunzos blew up the two pods with torpedoes. Satisfied that he'd killed the criminals, Tunzos promised Kirk that they would meet again. (TOS comic: "Double Bluff")
Alternate realities
In a timeline where the Onlies Earth originated and human civilization fell in the 20th century, Captain Tonzos commanded a fleet of the Klingon-Andorian Compact, reporting to Andorian Admiral Revethanis ch'Naras. He served in the War of Kentin, heroically as he recounted it. He met Kirk in 2274 when the Enterprise swapped realities with the VHC Muroc ringship near a Vedala asteroid. Tonzos escorted Enterprise to Regulus, where he enjoyed various meats and Orion company. Kirk resisted aiding or providing advanced technology to the Compact in their struggle with the Vulcan Protectorate, and Tonzos warned that Klingons had a tendency to take what they wanted if it wasn't freely given, particularly with Enterprise undergoing repairs in their spacedock. The conversation spurred Kirk to find a way to depart and return to their reality. (DTI novel: Forgotten History)