swapping meshes

im making a fighting game and when a character punches or something instead of them moving i want it to be instant like in retro fighting games, so instead of having an animation i would just swap the mesh (the animations are broken in my 3ds max anyway). i could just delete the old mesh and instantiate a new one but there must be an easier way so does anyone know it?

you can make two or more geometry on each other a simple disable all renderers except one. whenever you need just re-enable them all to another combination to get another renderer enabled