Sophic League power, artisan, and pozen master who, over a span of five centuries during the late ComEmp and Re-evaluation age periods, carefully crafted some half-a-million nanotech characterbots, each designed to perfectly mimic a real or fictional character in the history of mindkind.
In Eir famous "E-Message to the Common Po" (a work that is unique for its time in that while addressed to first and second singularity powers, has at least 5% of the content that can be understood be even an unaugmented baseline) The Pozer says "Every sentient, whether real or imagined is a koan. Solve the riddle each sentient pozes and learn where the Buddha of the Excited Hydrogen Waveform goes when the electrons are in their ground state."
Unfortunately, a number of the bots (despite being bioborgs, the suffix -bot was often appended, apparently as a joke), including Jacktheripperbot, Charliemansonbot, and Ukkahanbot eventually had to apprehended and deactivated by the authorities, following a number of murders (fortunately all victims had backups and were restored to life). However, Lectorbot managed to elude the authorities and is still believed to be hiding out in the Perseus Rift. Others, like Caligulabot, Torquamadabot, Hitlerbot, and Quanenderbot, were easily apprehended by local hyperturing authorities when they tried to stir up the baseline population and establish local autocracies.
Shakazulubot had more success in Nuizuluorbital (Solar Dominion), where he managed to pass for their local old earth folk hero, and Genghiskhanbot disappeared into the old Biovirate volume, and hasn't been heard of since.
Beowolfbot was believed destroyed when fighting a local perversity counterspinwards of the STC outer volumes, Ramabot failed to establish a local polity in the Terragen Federation, despite potent foglet powers, and Einsteinbot found that relativity and quantum physics were now ancient history. Jeanbeloitsampson bot likewise failed to create a new corporate empire, finding emself totally outclassed by the local NoCoZo businessbeings.
In a few cases, one borg tried to destroy another. Buffybot managed to slay Draculabot (who had up until that time managed to elude the authorities), but was less successful with Lestatbot, who is currently believed to be hiding out among a colony of vampire tweaks. Rambobot meanwhile was totally unable to kill Fumanchubot, despite enlisting the aid of Dirtyharrybot Quakeyoubot, and Cybi28bot, although this was more because the local customs vecs disapproved of the large quantity of nanofabricated weapons and several warchives in their possession, and alerted the police. And by the time Bondbot had arrived, Fumanchubot had disappeared, possibly with the help of Darthvaderbot.
With some 18% of the Pozer's borgs known to be destroyed, 15% deactivated and residing in various museums or research labs, and another 39% missing or untraceable, it is not likely the Pozer's koan will ever be solved. Nevertheless, there is a subculture of enthusiastic S1s, and even baselines and superiors, who still pursue the quixotic quest of the Pozer.