Mordekaiser Ultimate

I have been playing mordekaiser for quite a while now,and I can guarantee you that he's ultimate is bugged.In season 6 the drake or the person you have under control would chase and hit people for you if you don't tell it on who to aim,But this season the champion is just bugged.The dragon some time just stand still and do nothing EVEN when I tell them who to attack.I hope this will be fixed because it sure it is hell annonying having your drake do nothing when it's so powerful.