Portholus |
Interesting discussion. Guessing the armor is designed to seal off the affected area if damaged either by some form of Nanotech that seals the hole or sections at joints seal up limiting the damage to just a small area (part of the arm/leg or a section of your chest). Guessing the nanotech version is better just to simplify things.
Bite attacks should not happen if they are in bubble helmets. Now if they are wearing some device that allows for the intake of oxygen but not wearing a helmet should still allow the bite attack (or the breath weapon in the case of a dragon given that it is probably not wearing a space suit but its scales are tough enough to allow to exist in a vacuum). Given the intelligence of dragons, it is a strong possibility that they will be able to come up with a way to travel in space or they adapted over time to handle the vacuum.