Fek'Ihri Invasion

The was a brief conflict between the Klingon Empire and Fek'Ihri Horde in 2409. The Klingon Empire was initially surprised at the appearance of the Fek'Ihri Horde; taking advantage of this surprise, the Horde quickly invaded the core territories of the Empire. After the Horde was repelled, an operative entered Gre'thor to defeat both Molor and Fek'Ihr, ending the invasion.

Prelude
A resonance signature found on Fek'Ihr near the end of the conflict suggests that the Hur'q may have been responsible for creating the Horde. In 2409, Molor and Fek'Ihr managed to open portals that allowed the Fek'Ihri Horde in Gre'thor to escape into Klingon Space. Due to ancient animosity between the Klingons and the Horde, the Horde was committed to attack any Klingons discovered and conquer the Empire. The first sizable invasion fleet appeared in the Norgh System, ready to attack the Empire.

Battle of Norgh
When the Horde arrived, they slaughtered all Klingons present in the Norgh System. Before their destruction, the Klingons informed Qo'noS that a massive battle was occurring. Chancellor J'mpok tasked an operative to assist the attacked Klingons in response. Meanwhile, most of the Horde fleet left to attack Qo'noS, leaving a small guard behind near the portals. The Horde also sent a small fleet to defend Boreth. When the operative arrived, the Fek'Ihri ships and portals in the system were destroyed, including the Fek'Ihri commander. The operative quickly returned to Qo'noS after the battle.

Battle of Qo'noS
The Horde immediately attacked Qo'noS upon arrival. The planet's defenses were nearly destroyed and the commander of the assault, D'Jar, launched an attack on the KDF headquarters on foot. The operative arrived and successfully destroyed the nearby Fek'Ihri fleet and portals. After protecting the nearby Klingon station from attack, the operative beamed down to Qo'noS. The Klingons successfully defeated all Fek'Ihri forces, including D'Jar.

Search for the Sword of Kahless
The operative learns of the Sword of Kahless so the Fek'Ihri can be defeated. In the Sanek System, the operative helps Kahless defeat attacking Breen forces. After boarding the and fighting the Breen boarders, the operative finds Kahless. Kahless tells the operative that he will help them enter Gre'thor and stop the Horde in the Boreth System.

Battle of Boreth
The operative enters the Boreth System and destroys all Horde ships present. The operative then beams down to Boreth and descends into a cave with Kahless, fighting all Fek'Ihri found. At the bottom of the cave, the operative successfully enters the Barge of the Dead.

Battle of Gre'thor
The operative defeats Herron and enlists the help of the Klingons on the barge to enter Gre'thor. Inside, the operative defeats the spectres of Cowardice, Dishonor, and Treachery before defeating Molor himself. With the assistance of Kahless, the operative enters another area of Gre'thor and defeats Fek'Ihr, ending the Fek'Ihri threat.

Aftermath
The damage to KDF Headquarters was extremely severe. The Klingon High Council was relocated to the Great Hall, and Klingon High Command was moved to several buildings nearby. The victory against the Fek'Ihri Horde later bolstered Klingon confidence of defeating the Iconian threat. Although there were several other appearances by the remnants of their invasion force, they would never have the strength to be a serious threat again.