If the 'battle damage' paint is on plain unpainted plastic, then something like isocol should be enough but never use paint thinners as it disolves the plastic. Isocol is soft enough to get rid of ithe paint and leave the plastic beneath unharmed, its also gentle enough for it to be forgiven of mistakes as it requires persistant rubbing.

If its on painte surface, you can't do much for it. All you can do is paint over it. If its on clear plastic, then Isocol should work equally as good but you have to be more gentle as transparent plastics are thinner and if you apply to much preassure it could crack.