[quote=drallinix]Edit: Also since Mifune is throwing a spear hand wouldn't the actual point of impact aka his hand be going more than subsonic considering. He isn't just lunging with his hand out he is literally lunging and throwing a spear hand at Herriman's throat.
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Actually no. Once Mifune goes airborne, any forward momentum generated by a punch is going to have an equal and opposite effect on the momentum of his body as a whole. Since he isn't grounded, adding the motion of a punch (spear-handed or otherwise) wouldn't be able to generate any extra force. The best he could hope for is to try and make the impact point as small as possible, which the spear hand would be good for until he lost enough momentum that he couldn't break through the next object he hits, at which point his hand shatters.