M'Chla class

The M'Chla-class was a Klingon starship class, a bird of prey vessel in service to various Great Houses of the Klingon Empire in the 2250s decade. 

Service history
Following roughly a century of relative peace, the Federation encountered M'Chla-class birds of prey when the Starfleet starship USS Shenzhou, and its reinforcements, were attacked by representatives of 26 Klingon Great Houses at the Battle of the Binary Stars on May 11, 2256. The battle had been instigated by the fanatic T'Kuvma to reunite the Klingon Empire by rallying its houses against a common foe and ushering local space into Burnham's War. 

Weeks after the battle, the House of Mo'Kai targeted the USS Malachowski, on a cadet training cruise at the time, in the Vulcan sector. Following the death of Captain Anton Schaefer, the senior-most cadet assumed command and the crew engaged in repairs before Matriarch J'Ula and the and her M'Chla frigates could overpower the Federation  light cruiser. The USS Sebrova arrived to assist the Malachowski, and the pair of ships repelled House Mo'Kai. 

Together, they traveled to the Arucanis Arm to rescue the USS Ticonderoga (NCC-1650), engaging further M'Chlas. 

Soon after, the Malachowski and the USS Glenn (NCC-1030) defended a science outpost in the Delta Volanis Cluster against Mo'Kai raiders. 

In November, six months after the Binaries, the Klingons attacked the mining colony at Corvan II again, after an attack earlier that year had ben repelled. The attacking Klingon birds of prey were destroyed by the USS Discovery. 

Participating in a series of ambushed on Federation patrols, a trio of M'Chlas were part of the attack on the USS Gagarin (NCC-1309). The Gagarin was lost with all hands despite support from the Discovery when a bird of prey fired a torpedo at the and hit. 

In December, a pair of M'Chlas transported the Great House leaders Dennas and Ujilli to a meeting with a Federation representative on Cancri IV. It was really a ruse by the Klingons to gain support by General Kol, son of Kol-sha. As a reward, all Klingon ships allied with Kol received a cloaking device. 

When the USS Discovery exchanged its location with the, mirror universe Klingon ships were also pulled into the primary universe. 

The Discovery was destroyed by the Klingons, and Starfleet Admiral Katrin Cornwell found only wreckage. 

In 2257, raiders of this class were among the first waves attacking Starbase 1 at the edge of the Sol system. Some of these vanished when J'Ula's weaponised mycelial network technology backfired. 

Nine months after Discovery went missing and shortly after the ship's return, several M'Chas were part of the fleet approaching Earth for the final assault. These bore the trefoil insignia of the Klingon Empire. 

J'Ula and her fleet of House Mo'Kai ships appeared in 2409 and went into hiding. This became a concern for the Alpha Quadrant Alliance following the end of the Tzenkethi Crusade in 2410. 

Starfleet de-classified records, and the AQA ordered its commanding officers to relive events of Burnham's War through holoprograms. This entailed combating countless M'Chla-class birds of prey. However, the process resulted in a new technology, the Beacon of Kahless, that could summon 2256-era M'Chlas and other Klingon ships to aid in any space battle. 

Also in 2410, the ISS Discovery appeared at Pahvo, and came under attack from Klingon ships of various classes. With assistance by the AQA, the Discovery was defended, and the Klingons retreated. 

When the Discovery tried to return to its own univese and time period, the Klingons launched another attack. The AQA sent the Discovery and the surviving Klingon ships back to 2257, albeit in the prime universe, where they destroyed each other. 

A week before stardate 87831.2, the Klingon High Council ordered KDF generals to have clases of the ''Discovery'#-era refitted or reconstructed as replicas at several drydocks. First among these were the M'Chla- and, outfitted with new technology shared by the Allied Cooperative Starship Development Board. The M'Chla was classed a tier 6 pilot starship bird of prey. (SS STO (Jayce's Interstellar: Around the Galaxy))

At some point, ships of the class were part of Federation-Klingon engagements involving vessels from different cultures and eras.