On 29 October 1888, a Russian Imperial train that had been carrying Tsar Alexander III of Russia and his family derailed near Borki station in present-day Ukraine. This incident would come to be known as the Borki train disaster.
Matching the train's speed with his horse, Nikolai managed to catch up and jump from the horse onto the train, traversing its length from above. He dispatched one of the Tsar's guards, who had been protecting the entrance to the inner car, and proceeded inside. After killing a second guard with his dagger, and interrogating another, Nikolai discovered that the Tsar could be found in the dining car.
Proceeding deeper, Nikolai killed several more guards protecting the dining car, with the aid of his hidden blade and rifle. From there, he prepared to burst into the dining car and shoot the Tsar with his rifle, however, to his surprise, the Tsar was absent, and only his innocent family were seated inside.
As he recovered from the shock, Nikolai realized the presence of someone behind him, after which Alexander III attacked him. Though the Tsar was able to secure Nikolai in a stranglehold, the Assassin was able to drive his blade into the Tsar's abdomen, though barely injuring the powerfully built man. He escaped, and the two faced off again.
During the struggle, the train suddenly derailed and careened off the tracks, tearing apart several of the cars. Alexander struggled to hold up the roof of the dining car before it could collapse on his family, ordering them to run before throwing the remains to one side.
He then approached the fallen Nikolai to finish the battle. He taunted the Assassin about killing his loved ones as he beat him, then left to rummage through the remains of the train, and eventually pulled a case from the destroyed dining car.
The Tsar then revealed the Staff to Nikolai, and asked if it was what he was looking for, before tossing it to the Assassin in challenge. Even though he no longer had the Staff in his possession, Alexander was able to disarm Nikolai and overpower him. However, hearing the calls from his family, the Tsar allowed Nikolai to escape, barely alive, in order to report his assassination as a complete failure.
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.
- Assassin's Creed: The Fall - Issue #1