During the Hussite Wars, Hynek initially fought with the eastern Bohemian Orebites; he was their captain. During the collision with the moderate Hussites in Prague, he was taken prisoner by them. However, a year later, he entered in their service. In 1423 he participated with his brother Victor in a campaign in Moravia. In 1425 he arrested Jan Puška of Kunštát, the marshal of Nymburk at Mydlovar Castle and kept him prisoner at his own Poděbrady Castle. The reason for the arrest was probably a long-standing land dispute between the Poděbrady and the Lisice branches of the Kunštát family. After Jan Puška died in his prison, Hynek appropriate his Mydlovar Castle and the associated Lordship of Kostomlat, and added it to his Poděbrady possessions. In 1426, he participated in the Battle of Aussig. When the Taborites besieged Poděbrady, he fled to Nymburk, where he died on 16 October 1426 of a gunshot wound. He was not married and left no descendants.