Slugterra Mecha beast Headcanons
The reason mecha beasts are modelled after animals from the surface is because humans don’t originate from Slugterra. When they went down they brought with them tales of animals that soon became myths that inspired the mecha beasts shape
There are also mecha beasts based off of now extinct animals (like mammoths), since the first humans in Slugterra arrived so long ago
There’s even some mythical creature mecha beasts, though these are few and far between as they’re often custom made (which is quite expensive)
The newer mecha beasts have less personality. The older the mecha beast the more they emote
This is why Pronto’s Donkey sasses him, as it’s an older model (older than the rest of the Shane’s gang’s)
Blite’s mecha beast would also be quite emotive, but due to the damage sustained over the course of its time in the cavern of time with no repairs, it no longer can (at least, not immediately noticeably)
The reason mecha beasts have less personality is because certain powerful people that didn’t treat their mechas with more respect started complaining, so mecha forges gave in and fixed the ‘issue’
Now it’s the normal, though some riders still prefer the personalities and can get their mechas modded
Different mecha beast animals have different uses, like donkey’s are typically used for hauling, horses for speed, big cats for agility, etc etc