Hero engineers.

How should a Mechanic develop? There are only three skill stacks available. You can take abilities for all three machines, and the hero will become a jack-of-all-trades, but ultimately weak. Regarding the machines individually: the Tent is a good support, but it doesn't heal very well, and the Plague Tent is nonsense, in my opinion. The Ballista is, of course, the most useful; it can replace Archers in the army in the early game. But there's also the Catapult, and without its skill, storming a Castle is practically suicide. Of course, this doesn't help much (my Catapult, for example, only shoots where it's supposed to half the time), but it's even worse with an "untrained" Catapult... So, the development path should be Ballista - Swift Ballista - Catapult? What about the Enchanted Ballista? What about Earthquake? What about Steal? What should be done with them?