Blood type is a variable in DayZ Standalone.
Every player has distinct blood type which is randomly assigned each time you spawn. A player's blood type can be determined by using a Blood Testing Kit. Simply equip the kit in your hands and you can test either your own or another player's blood. All players involved must stay still, else the action will be cancelled.
Possible blood types include O-, O+, A-, A+, B-, B+, AB-, AB+.
 Blood Type Compatibility
To perform a successful blood transfusion using a Blood Bag Kit, a donor's blood type must be compatible with the recipient's for the transfusion to be beneficial. Incompatible blood type will lead to instant death for recipient.
As a rule for memorization:
- O can transfer to O, A, B or AB
- A can transfer to A or AB
- B can transfer to B or AB
- AB can only transfer to AB
- (-) can transfer to (-) or (+)
- (+) can only transfer to (+)
- O- is the universal donor and AB+ is the universal recipient