You’re squared off against your foe. You’re usually a good shot, but the rain is coming down pretty heavily and besides, you need to do some long division in your head if you’re going to get that bomb defused in time. Not to mention you’re bleeding pretty bad from the gunshot wound your foe gave you moments before.
A shot rings out, and you both fall.
Luckily, you manage to drag yourself to the bomb and type in the code before you pass out from blood loss. You wake up in the hospital and the doc is about to give you a transfusion. You thank your lucky stars for Karl Landsteiner, because without him there was a good chance you wouldn’t survive the procedure.