Khutulun regularly accompanied her father on military campaigns, reportedly charging into enemy ranks and seizing captives with her bare hands, according to Marco Polo's account.
According to the accounts of Marco Polo, who claimed to have met members of Kaidu's family during his travels through Central Asia, Khutulun was a constant presence on her father's military campaigns, riding into battle alongside him rather than remaining behind as was customary for royal women in many neighboring cultures.
Polo describes her as displaying extraordinary bravery, at times riding out from the ranks of the army to seize an enemy soldier with the same ease as "a hawk swoops down upon a bird," taking captives with her bare hands in full view of the assembled troops. While the exact date of any single engagement cannot be pinned down, this pattern of participation is treated by historians as a defining and recurring feature of her adult life, beginning in her youth and continuing for decades.
Her role went beyond mere participation: she was reportedly a trusted military advisor to Kaidu, who consulted her on strategy, and command duties were sometimes given to her over some of her many brothers, an extraordinary degree of authority for a woman in the 13th-century Mongol world. This reputation for martial excellence cemented her legendary status among both Mongol chroniclers and European travelers, and she became emblematic of the unusual freedoms and power available to elite Mongol women during the height of the empire.