In this WWII Prequel, the Empire of Japan and the Soviet Union fight over the Mongolian border, a stretch of lifeless steppe with no cover, trees, or established supply lines. In what has been dubbed a "border conflict" tens of thousands of men, thousands of trucks, and hundreds of tanks are rushed to the frontline that only barely escapes spiraling into a much larger war...at least for a few years.
Sources:
Edward Drea. Nomohan: Japanese-Soviet Tactical Combat, 1939.
Edward Drea. Tradition and Circumstances: The Imperial Japanese Army's Tactical Response to Khalkhin Gol.
Glenn Barnett. Russo-Japanese Clash at the Battle of Nomohan. WWII History. May 2005. 4#3
Amnon Sella. Nomohan: Khalkin Gol: The Forgotten War. Journal of Contemporary History (1983) 18#4
Anthony Beevor. The Second World War.
Alexi Shishov. Russia and Japan. The history of military conflicts
