The question of the day is: how can I make an immobile blob be an effective supervillain in a dramatic storyline?

This character is bound to a mobility device 24/7, whether it be a hover chair or a high-tech scooter. The villain practically lives in the chair, and with flagrant disregard for both the highly corpulent state of their body and the absurd amount of food they eat in one day, it's clear that the villain does not plan on ever getting off of it, feeling quite content to stay in a sedentary position all day (Not like this tub of lard would be able to stand on their own anyway.) As the villain eats more over the course of the story, the villain weighs far more than they did upon their introduction.

Being immobile, this villain's actions are obviously limited. However, the villain is not concerned about their mobility issues because they have their chair/scooter for reliable transportation. Additionally, the villain commands an army of robots to complete various tasks around the headquarters, meaning their own requests get satisfied and their own responsibilities get fulfilled, and the villain doesn't have to lift a digit. The robots assist with dressing their boss, washing their boss and executing their boss' nefarious plans.
Not to suggest that this villain lacks agency altogether, as although the villain's arms look huge and heavy, they can still lift and thus use them - mostly for handling food. Still, the robots do a majority of the work.

This villain is a technological genius who independently designed their own mobility device and robot army. The villain likely knew that their gluttonous habits would inevitably result in immobility and thus spent time preparing for it.

The villain doesn't even need to be close to the heroes. A monitor is all they need to communicate with the heroes, taunting and teasing the heroes from afar. This screen could also be how the villain is able to somewhat participate in the action if the robots bring the screen with them to a set location. I've always imagined a scene like this being a highly intelligent yet mobility-impaired character translating ancient text virtually through a screen.

Sequentially, the heroes first fight a wave of robot-fighters before finally fighting their big-bellied boss. But despite appearances, the villain's masterful control of their mobility device and skill in wielding a powerful weapon makes them a bigger threat than they realize.

The villain also knows how to use their immense weight to combat the heroes in a fight.
- Aggressively ram into the hero at full speed.
- Press the hero into a barrier with their big, bloated belly.
- Ample padding for protection against projectiles.

The mobility chair/scooter is also decked out with weapons which can activate with the press of a button or switch.
- Lasers in the armrests.
- Razor-sharp blades that protrude from underneath.
- Spikes on the back.

The villain might spin around in a circle with a blade extended underneath the platform.

And they say any food heals you in video games, so... XD

Regarding motives... I'd need to do some more research on what makes fictional supervillains act the way they do.
- Causing chaos and controversy for the sake of shaking society up?
- Having an altruistic goal but morally questionable methodology?
- Hunt someone down and enact revenge for a wrongdoing committed in the past?
One thing I would like to keep, though, is that the villain's motivation has nothing to do with their extreme gluttony or weight gain fantasies.
- No stealing food for the sake of satisfying a sick pleasure.
- No stealing money in an attempt to maintain their uber-gluttonous habits.
- No frustration about fat-shaming.
Trying to stay on brand with my writer's creed by creating an effective supervillain who "just so happens to be a gainer."

I'm envisioning an evil blob sitting in front of a large series of monitors, barking orders at robots frantically operating numerous systems on a vast dashboard. All the while this blob is gorging endlessly on everything.