Kimah led the Sharnazim before ascending to the throne as Zakhan of Vassagonia with the the death of Moudalla in MS 5055. He reigned for six years, during which time Vassagonia served as the only major ally of the Darklords of Helgedad in their campaign to conquer central Northern Magnamund.
Vain and arrogant, Kimah possessed incredible willpower and he could hide his thoughts even from a Darklord, a trait that allowed him to negotiate being given the Orb of Death by Archlord Haakon in exchange for both Lone Wolf and the Book of the Magnakai even though he had possession of neither at the time. Events surrounding Kimah after his receipt of the Orb are unclear: the Legends of Lone Wolf novels tell of Kimah's imprisonment in his own torture chambers by Drakkarim and the throne's passage to a popular rival, while there is no indication that his rule meets with any interruption in the timeline set by the game books.
What is known is that Kimah personally led Vassagonia's armored legions during the Siege of Tahou in MS 5061, during which defending soldiers found that the Orb of Death made him invulnerable to ordinary weapons. Kimah used the Orb of Death to destroy Tahou's west gate, gaining entry into the city. He encountered the Kai Master Lone Wolf in the city, who possessed weapons that were capable of penetrating the Orb's shield. Lone Wolf won the ensuing duel, killing the Zakan. His death led to the collapse of his oppressive regime and the withdrawal of Vassagonian troops from all of the lands that they had previously occupied in support of the Darklords' campaign of conquest.
In the original edition of the books, Zakhan Kimah had a combat skill of 44 if engaging with the Sommerswerd. This extremely high combat skill caused some controversy: the maximum possible combat skill for a player who had completed every preceding book as well as acquired all possible CS-boosting items was only 38 (19 natural +3 weaponmastery +2 shield +2 Silver Helm +1 Lore Circle of Fire +3 Lore Circle of Spirit +8 Sommerswerd), or 40 with an Alether potion. The -4 combat ratio meant Lone Wolf would lose endurance points at the same rate as the Zakhan, and very likely meant death, especially since Lone Wolf would have just been hit by an energy bolt before combat (taking 5 endurance points of damage). Even if Lone Wolf chose not to equip the Sommerswerd, Zakhan Kimah still had a very high combat skill of 34, and is very hard to beat.
In the revised Mongoose editions, Zakhan Kimah's stats were toned down, making him significantly easier (but still challenging) to defeat.