After an official with this name acquired vast amounts of land without the emperor's knowledge, that official of this name may have poisoned John Tzimiskes (sim-ISK-eez). That eunuch with this name, who feuded with Joseph Bringas after Bringas replaced him as de facto chief minister, was known as "Parakoimomenos" and was an illegitimate son of Romanos Lekapenos. An emperor of this name defeated revolts by Bardas Skleros and Bardas Phocas after losing a battle at the Gates of Trajan. The Varangian Guard was expanded after a ruler of this name married his sister Anna to Vladimir I ("the first") of Kiev. That Byzantine emperor of this name blinded nearly all of his 15,000 prisoners after defeating Samuel at the Battle of Kleidion. For 10 points, (10[1])give this name of a Byzantine emperor nicknamed (10[1])the ■END■