X-Antibody

The X-Antibody (X抗体 X-Koutai) is a vaccine that makes Digimon immune to the X-Program. They are also more powerful than their non X-Antibody counterparts. Usually when a digimon is introduced to the X-Antibody they like stated before become more powerful and usually gain a crystal like object in their forehead. Some digimon like Dorumon are unaffected by the X-Antibody because they are "born with it".