- "He thinks I do not know, but I do. The blood will protect me."
- — Edward Richtofen
The Blood Vials are an important set of items featured in the Zombies mode of Call of Duty: Black Ops II, Call of Duty: Black Ops III, and Call of Duty: Black Ops 4. They also appear as a special item within Blackout.
During the Aether storyline, the Blood Vials would play a critical role in Primis Richtofen's goal for survival, utilizing the vials as a sort of insurance policy for the future. Initially, Primis Richtofen instructs his future undead version to secure the blood samples of Victis for the rest of Primis while he would secure the blood of Salvatore "Sal" DeLuca and Michael "Finn" O'Leary. With the blood vials of the two mobsters, Primis Richtofen would deliver them to his past self, explaining that they would help him in the future. Returning to his lab under Alcatraz Island, Richtofen would soon be delivered the blood vials of Victis before handing them off to the future selves of Primis after they obtained the soul of Ultimis Takeo. After future Primis returns to Zetsubou No Shima, Richtofen explains that the blood is an insurance policy for the future.
After collecting the soul of Ultimis Nikolai and traveling to the House, Ludvig Maxis accidentally unleashes the Shadowman from within the Summoning Key, allowing the Shadowman to turn Doctor Monty's "perfect world" into a set of floating land masses in space beneath the Apothicon sun. Prior to battling the Shadowman, Richtofen and the rest of Primis each consumed a single vial, allowing them to remain in Monty's world after the Shadowman was destroyed. Despite this however, Monty simply sends Primis back in time to The Great War, ultimately creating a cycle in time.
However, things would soon take a turn for the worst for Richtofen. When Primis arrived to collect the blood vials containing Victis' blood, the lone Richtofen there handed his future self the Kronorium, where it is soon revealed that the book has changed, causing Richtofen to panic upon reading that his blood was needed. After Primis is captured by Brutus, they learn that their blood would be used to open a gateway to the Dark Aether, allowing the Apothicons to return. However, they are able to break free thanks to the help of the ghost of Albert "Weasel" Arlington, where they soon head to Richtofen's Lab. There, they unlock a hidden cryopod before engaging Brutus in a final battle around the Dark Mechanism. During the battle, Richtofen sacrifices himself and enters the device, allowing the device to begin to siphon off his blood while another version of himself awoke in the recently-revealed cryopod. After the Great War Richtofen uses a stone to purify and free the souls of Alcatraz, he hands Nikolai the Kronorium before confronting his past self, who was still in the Dark Mechanism.
While initially happy that he wasn't going to die, the Great War Richtofen reveals that the cycle is broken, saying that their insurance policy was no longer needed before taking the blood vials off of Primis Richtofen. Horrified over this outcome, Primis Richtofen could only watch as the remaining blood vials given to Primis were soon disposed of before watching his former allies leave in separate portals. Remarking that he was the "nicest" Richtofen and that no one will ever remember him, Primis Richtofen soon dies from blood loss in the Dark Mechanism, effectively breaking the cycle caused by his actions.
A pair of Blood Vials can be obtained as a special item in Blackout, where they are used to obtain Richtofen as a playable character. In order to acquire them, the player must travel to the Asylum with another special item relating to another character mission in the player's inventory. The player can then interact with the blood fountain in the center of the Asylum, causing the item in the player's inventory to be removed and rewarding the player the Blood Vials, to which the player can then pick up. With the Blood Vials, the player must reach a placement of fifth in Solo, third in Duos, or second in Quads. After reaching the necessary placement and the player finishes the match with the Blood Vials in their inventory, Richtofen will be unlocked as a playable character.
Alternatively, the player can obtain the Blood Vials by killing a Blightfather when it appears at the graveyard by the Asylum.