Corthas Muhleer was an infamous mage who was perhaps the person known for holding the title of Magister for the shortest period of time in history. Corthas held the tile for less than a full day in 246 DR, perhaps not even long enough for his soul to be treated as a Magister by Mystra in the afterlife.
Corthas was ruthless in his approach to "ruling the world."
Though he was able to slay his predecessor, Brymmyn Thorl, Corthas exhausted his physical and magical strength during the duel. He fell into a deep sleep within Brymmyn's castle after the duel, waking to find that a rogue wizard had stumbled into the stronghold while he was recovering. Through blind luck, the intruding wizard, Galeerie Mulurkrath, had accidentally stumbled through the dangerous traps scattered throughout the keep. Galeerie was ascending a stairway when Corthas came running down from the opposite end. Galeerie picked up a sword he found on the steps and slew Corthas where he stood, giggling along the way.