There's occasionally technology in Mega Man games, usually on the Wily Capsules, that let a robot or device go completely invisible. Ghost Man was born from me thinking it would be funny to give this technology to a Robot Master, and then cover it with a blanket. It would create a nice illusion of a traditional sheet ghost.
They would work in a haunted house, basically being both an employee and a prop at the same time. Their torso can extend to make it look like they are flying around, and the (unweaponized) Ghost Wave could interact with other props in the attraction, like knocking something over while they distracts guest to get a cheap scare.
Ghost Man doesn't like their body being visible. If this project ever became an actual game, Ghost Man would be weak to Paint Man because it would prevent them from going invisible.
Because the invisibility made me put this one together a bit differently, here are some bonus pics:
pose, invisible (how they normally look)
pose, visible
neutral, visible
The main body. The head contains the cloaking tech, and the chest generates the Ghost Wave.
