I know the obvious issue for some people is that mechanical pets aren't beasts. But the rules have been relaxed in regards to what we can tame and now hunters don't even "need" a pet. And with Gnome hunters being a high possibility in the future I think it's time to explore the possibility of engineering hunters to utilize robots in lieu of organic pets.

I imagine a manual item for engineers to collect similar to learning how to tame the Direhorn. The manual teaches its user to "hack" into a variety of robots to convert them into full-time pets. Mend Pet turns into "Repair X(Robot/Pet/Construct".

I can also see Gnomes an Goblins possessing the ability to take command of mechanical pets innately as it would fit them for a perk.