Nikolai is an steam locomotive built for the Russian Railways in the 1890s. He was taken as a spoil of war by the Germans on the Eastern Front of World War One but was stolen by the Americans again during the Hundred Days Offensive. After the war, Nikolai was sold to Lucky's Yard as a shunting engine, where he works today.
Nikolai is a very grim and quiet engine, and trusts no-one. His motto is; 'If they aren't myself, I cannot trust them', alienating him to everyone except Big Mac, who is his only real friend. This came after Big Mac saved Nikolai from coming off when the Toptown Bridge washed away one spring.
Nikolai is based on a O class 0-8-0, except he has buckeye couplings and has been reguaged to standard guage for use on the Dock Railway.