 Jurchen horsemen were provided with heavy armor; on occasions, they would use a team of horses attached to each other with chains ("Guaizi Ma").As the Liao dynasty fell apart and the Song dynasty retreated beyond the Yangtze, the army of the new Jin dynasty absorbed many soldiers who formerly fought for the Liao or Song dynasties.The new Jin empire adopted many of the Song military's weapons, including various machines for siege warfare and artillery.