- "I suspect there are other moles in the organization. Dr. Harvey Yena, and Dr. Peter McCain to be precise. "
- — Harvey Yena's first mentioning, by Edward Richtofen.
Doctor Harvey Yena is a character featured in the Aether story of Treyarch's Zombies mode. Yena was first mentioned on the map Call of the Dead from Call of Duty: Black Ops and was also mentioned on the map Gorod Krovi from Call of Duty: Black Ops III. He then spoke in Call of Duty: Black Ops 4 and was featured in several radios.
Harvey Yena began his work with Group 935 on May 18th, 1943, acting as a spy for the United States of America alongside Peter McCain, who was stationed in Verrückt while Yena was in Siberia. During the war, he created the Scavenger and its upgraded version the Hyena Infra-dead. He also created the vodka concoction which resulted in Nikolai Belinski becoming responsive to Group 935's testing.
After the war and the dissolution of Group 935, Harvey Yena decided not to go back to the US and instead was hired by the Soviet Union and established the Ascension Group on January 29th, 1946. In 1958, he helped retrieve the blood of an Apothicon located at the bottom of the Ocean per Pablo Marinus' request. However, rather than give Pablo the blood, he was convinced by Doctor Anton Gersh to keep the blood so they could test it for experimentation. On New Years Day 1964, he attempted to bring the blood back to Pablo and then return to the United States, but the Apothicon Blood converted the crew of his ship into Zombies, who shortly afterwards killed Doctor Yena.
When Primis (Edward Richtofen, "Tank" Dempsey, Nikolai Belinski, Takeo Masaki from Dimension 63) arrived at the Der Riese facility and Richtofen killed his Ultimis self, moments after he teleported away Ludvig Maxis and his daughter Samantha, it triggered fractures across space and time.
In the Agonia fracture, dragons created by Division 9 were released on Stalingrad to break the stalemate on the Eastern Front. Harvey Yena was transferred to the city to continue the Die Glocke research. He reported the possibility of "time displacement" and "movement across dimensions".
A letter signed by Harvey Yena can be found on Gorod Krovi, it reads:
The dragons continue to bring success in the Eastern front. Russian resistance is fierce but we are maintaining a stronghold in Stalingrad. There are rumors of a new push to retake the city, but I am confident it will be stopped. The Hatchery continues to experiment with ways to enhance the beasts even further. Group 935 will not be technologically outpaced by the Russians.
Die Glocke research continues to inspire new theories of time displacement and possibly even movement across dimensions. Security has been enhanced, especially after the disaster that was enabled by Doctor Groph’s lax security measures. We have taken steps to ensure that none of this technology falls into enemy hands.
However, I feel I must protest the behavior of this insufferable apparatus that we have been forced to contend with. Sophia, as IT likes to be called, has demanded that we change the password to an encrypted cipher consisting entirely of unintelligible characters for maximum security. The current method is sufficiently secure without getting in the way of researchers performing their duties. Even if someone were able to obtain one of the special code cylinders, they would still need to know the password. While it is possible it could be guessed, it is easy for our researchers to remember due to its association to our Die Glocke research. Still, I feel it is sufficiently obscure that no one should be able to guess it easily.
Harvey Yena, Sc.D."
- The character is associated with the developer Mark Maestas, as well as the animal Hyena. Observe that Harvey Yena can be written in shortcut as H. Yena.
- In Shadows of Evil, shooting down Maestas's picture in the boxing gym with the Crocuta (Pack-a-Punched Kuda), another name for Hyena, will drop his picture off the wall.
- Mark Maestas's Twitter account had carried the image of the Black Ops 4 perk Scavenger, who showcases an Hyena. This is a double reference, as Harvey Yena is considered to be the inventor of the Call of the Dead wonder weapon, the Scavenger, who is Pack-a-Punched name is "Hyena Infra-dead".
- The word "HYENA" appears to be a part of the key of the ADFGX cipher from Mob of the Dead's loading screen.
- The word "HYENA" can be seen on one of the chalkboards in the map Der Riese from Call of Duty: World at War.