A hwacha cannot move and attack in the same turn. But it can do it when it accompanies a Great General. It seems the +1 movement bonus from a Great General is converted to an opportunity to attack in the same turn. Sav file was attached for test and reproduction. There are 3 hwachas which surround and attack Handan. The leftmost one, with Great Genenral, can both move and attack in the same turn. If Great General is separated away, it becomes normal.