The Haunting of Verdansk was a special event in Call of Duty: Modern Warfare and Call of Duty: Warzone available between October 20th, 2020 and November 3rd of the same year during the Season Six of content for Modern Warfare. 
With the release of the Haunting of Verdansk, the map of Verdansk received an update turning it into a moonlit and haunted version of itself. The map featured puddles of blood dripping from ceilings, ghosts in buildings, and a ghost train in some locations.
Night-time Verdansk could be played in a special playlist. The event also featured an exclusive mission called "Trick of Treat" where people would open supply Supply Boxes in specific locations in Verdansk for a chance to get a Halloween-themed item. A new limited-time mode was also released in Warzone with the event, Zombie Royale. New store bundles inspired by the The Texas Chainsaw Massacre and Saw movie franchises were released during the event.
Trick or Treat Mission
During the event, a mission called "Trick or Treat" was available for the players in Warzone. Players had to open Supply Boxes at specific locations in Verdansk for a chance to earn a specific reward. When all 16 rewards were collected, the players were rewarded with the Legendary "Pumpkin Punisher" Grau 5.56 blueprint. However, a jump-scare sequence also has a chance of occurring instead, temporarily leaving any victims vulnerable to attacks from other players.
|Epic||Calling Card||"Spooky Scene"||Storage Town|
|Legendary||Watch||"Time of the Season"||Dam|
|Epic||Oden Blueprint||"Return To Dust"||Military Base|
|Epic||Calling Card||"Pumpkin Peril"||Hospital|
|Legendary||Combat Knife Blueprint||"The Cleaver"||Gulag|
- "Be the last team with a human alive to win. Players turn into Zombies on death, but can redeploy as human by collecting syringes"
- — Zombie Royale description
Taking place in Verdansk during night, Zombie Royale supported up to 150 players in trios. When killed, a player would turn into a zombie and redeploy in the map instead of being sent to the Gulag.
As a zombie, a player could only attack human players who are highlighted and their footprints remained temporarily visible. While Zombies were somewhat weak, being unable to use armor plates, they had three different actions at their disposal:
- Charged Jump which allowed them to jump to high places quickly. The longer the jump was charged, the higher the jump was and the cooldown until the next Charged Jump.
- Gas Grenade which disoriented the enemy living players and made them unable to use weapons when inside the gas cloud.
- EMP Blast which destroyed enemy electronics and disabled vehicles, digital optics and player HUD within its blast radius.
Human players dropped a syringe of Antivirals upon death; if a Zombie player retrieved two Antivirals, they would be sent back into the map as a human player again. However, if a zombie is killed they must be redeployed by a human squadmate.