The key to the success of the Mongol Empire was its fighting tactics. The images below display the Mongol campaigns and four of the military tactics Genghis Khan created. He developed and refined these tactics over his various military campaigns.
All pictures can be clicked on to enlarge them.
The picture above is of the various Mongol campaigns and the countries shown existed in the time range of 1223-1242.
All pictures were found on, https://www.behance.net/gallery/7250171/Genghis-Kahn-Military-Tactics