Bug: Eruptor Merc behavior algorithm fails when unarmed

Bug Report Reference Number: 709,266,838
/debug number: Bug Report ID: #2219372096

Though my Eruptor merc has skills he could use while unarmed, if I unequip my merc's weapon, his algorithm fails and he only runs in place instead. The merc does not use his warcry, molten shell, or consecrated path. He teleports to my location when I cast "Order: To me!", but then continues running in place in the direction he was last headed without regard to player inputs or positioning.