Just wanted to say something about the post regarding Arthur's arm - if I remember correctly, the prosthetic should actually be placed a little higher than the injury for it to hold on, so he would probably have his arm down to his mid-bicep. Sorry if this is wrong or doesn't make sense, English isn't my first language .-.
Its possible. Hard to tell much about it cause we dont really know how ‘realistic’ it is. If its like, full on automail style impossibly advanced and actually grafted to his body, or just slightly more advanced then what we currently have and sits on his arm/shoulder with straps and such.