Through the use of the Hot Air Balloons and Advanced Balloon cards available to European nations, a player's Explorer gains the ability to release Hot Air Balloons. The Colonial Age balloons will remain active for 20 seconds, and can only be used once a minute, but may be called out an unlimited number of times. The Industrial Age balloon remains active permanently.
The Hot Air Balloon is an exploration unit that hovers above the ground and shares the same Line of Sight as a Monitor (38). Its Line of Sight can be increased to 50 through use of Town Watch and the Spanish card TEAM Inquisition. The Hot Air Balloon may only be sent from the Home City and then dropped on an area by the Explorer. Due to being invulnerable and lacking any attack, the Indian card Shivaji's Tactics is completely useless on the unit.
It cannot attack and it cannot be shot down. There is no effective counter for the use of balloons with the exception of downing the enemy explorer as often as possible
Hot Air Balloons can be dropped on any area of the map instantly; it does not have to be a location near the Explorer. This means it does not have to fly over enemy walls; it can appear behind them and then begin scouting.
Balloons are capable of capturing Herdable animals, or stealing them from the enemy if undefended.
“Joseph and Etienne Montgolfier are to hot air balloons what Orville and Wilbur Wright are to airplanes. They believed that their balloons were held aloft by smoke, burning hay and even shoes to keep early balloons up. Within just a few years, balloons appeared on the battlefield to scout and observe enemy movements and deployments.”