When Runner accesses Doppelganger Antibody, you may pay (2) to give Runner a Doppelganger counter, even if Doppelganger is not installed. Ignore this effect if Runner accesses Doppelganger from the Archives. Each Doppelganger counter causes Runner to lose (1) at the start of each of his or her turns. Runner may take an action to pay (4) to remove a Doppelganger counter. If Doppelganger is accessed from R&D, Runner must show it to you.