In 1888, the Mentor tasked Nikolai Orelov to assassinate Tsar Alexander III, an ally of the Templar Order, while the latter was traveling by train from the Crimea to Saint Petersburg. However, Nikolai's assassination attempt ultimately failed, with the Tsar managing to disarm and overpower him. However, the Tsar chose to spare Nikolai's life and allowed him to escape, barely alive, in order to report his failed assassination to the Order. Despite Nikolai's failure in assassinating the Tsar, the wound that Nikolai inflicted on him would eventually cause inflammation in Alexander's kidney. As a result, Alexander passed away from kidney failure in 1894.
In 1908, the Mentor once again hand-picked Nikolai to retrieve the Imperial Sceptre, one of the Staves of Eden, from a Templar research facility in Tunguska, where it was being tested with electrical machines based upon designs stolen from their ally, Nikola Tesla. Ultimately, the facility was destroyed in a massive explosion while the Staff and the Assassins were still inside it, with Nikolai being the only survivor.
In December 1917, the Mentor personally hired at least one member of the Brotherhood into a community of scientists, revolutionaries and Assassins at a facility in Protvino provided by the Russian Academy of Sciences, informing her about how the Academy was founded in Saint Petersburg by Peter the Great in the 18th century, after intense lobbying by Gottfried Wilhelm Leibniz.
In 1924, after Vladimir Lenin's death and Joseph Stalin's takeover of the Soviet Union, the Templars, through their control of Stalin, took over control of the Soviet Union. During this time, the Mentor went into hiding. However, he swore he would continue to give orders from seclusion, jokingly referring to it as his retirement.
In 1926, the Mentor tasked Sergei with tracking down Nikolai, who had left the Brotherhood and fled Russia with his family, taking the shard of the Staff of Eden that was destroyed in the Tunguska explosion with him. However, Sergei, after successfully finding Nikolai, was ultimately overpowered and killed by Nikolai.
Following the end of World War II, the Mentor continued to lead the Assassins as they struggled to regain their footing, although the Brotherhood ultimately succeeded in poisoning Stalin on 5 March 1953, making it look like a stroke. However, the Mentor suddenly died sometime in or before June 1953. Following his death, the Brotherhood, now lacking a strong leader, was left aimless and started to lose influence in the government, as well as funding for their projects.