The title say it all. We should be able to choose whether or not to send the mech along the army.
Once you can do heroic dungeons with 1% HP he become quite the dead weight, one than take ressource. He is not worth the 5 soul spend hiring the mechanic and yet he is not even worth the time spend taking care of him manualy but then that may be just me being lazy ahaha ...
I'm light green with 1% for heroic dungeons 6 so sure his 15k stats may help getting to dark green but if given the choice, i would farm heroics 5 longers than carrying this dead weight and heroics 6 isn't exactly my problem as i still miss my first legendary xD