Hy.. I am sure you woldnt fix this but you should know. I have a Warlord and i am using Polearm that suposed to hit all mobs in front of me but it seems i hit only one so warlords or destroyers cant make trains with taking HP from only 1 mob
works fine with dwarves
warlord has a self buff(toggle) that makes pole to hit only 1 target, check if you are using it (Focus Attack if i'm not wrong)