Neat and perfectly matched with M-Bot's character.
But I think he needs ears. Sonar Ears that are pricked like a bad-ass Doberman.
Cause right now he kinda looks like a mutated hump-backed crocodile.
If he had those ears, the K-9 unite look would be instant connection to the viewer.
His chin could have slit holes that act as a dog's nose. He'll be able to pick up scent as well, trace amounts of oil and skin that have the DNA of his next victims.
Almost as if he would look better if his head was upside down, so the chin becomes his nose and gives the defining features of a dog's snout. And the ears would flip up.
The arched on his back is good because he could also be a rescue unite, carrying pedestrians and wounded away from a crossfire. It can also double as a saddle seat for riders such as Pico.
And just for kicks...why not have the ability to shit grenades/landmines?
(Okami reference - exploding poop)
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I would love to see M-Bot's animated transformation like you did with the tank.
Idea - you should make a postcard featuring all the Bots. Including G-Bot, F-Bot, and your version of Angry Faic Bot.