A Klingon actor portraying Molor
According to Klingon legends, Molor was a tyrant that ruled over Qo'noS during Earth's 19th century. In his honor, living sacrifices were once made at shrines built above the seven chimneys leading into the underground volcanic tunnels beneath the planet's surface. He was believed to be so strong that no one could oppose him -- until his defeat by Kahless the Unforgettable.
Molor was said to have sent 500 warriors to assault the city of Qam-Chee, an army so great that all of the city's warriors fled except for Kahless and Lukara. The two of them stood alone against the army and emerged victorious -- sparking what was known to be the greatest romance in Klingon history.
Shortly after the wedding of Kahless and Lukara, Molor sent an army to attack them again. Though the pair were victorious once more, they almost died. This battle inspired the tradition of wielding ma'Stakas at the end of marriage ceremony.
The final battle between Molor and Kahless was fought at the River Skral. Kahless killed Molor with the first bat'leth, the Sword of Kahless. The annual Kot'baval Festival was a celebration of Molor's defeat.
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Molor is derived from Star Trek. For canon information, please visit Memory Alpha.