Thomas and Andrew participated in the disastrous Battle of Mohi on 11 April 1241, when the invading Mongols destroyed the Hungarian royal army. Béla IV narrated the Hont-Pázmány brothers' actions in his charter in 1253. Accordingly, when the monarch fled the battlefield, Andrew handed over his nimble and full-strength horse to Béla IV, lagging behind on foot, turning to the pursuers. While Thomas was killed in the site, Andrew managed to survive and went into hiding.