Warzone Haunted Hollow Mystery Box is not a normal fixed box sitting permanently in one building. It appears on the Ghost Train after players use a train signal to stop the train and phase it back into reality, creating a limited window to board and use the box before the train becomes immaterial again.
That makes the Warzone Haunted Hollow Mystery Box part of the Ghost Train activity rather than a separate point of interest. If you are searching random rooms around Haunted Hollow for a Zombies-style box, you are looking in the wrong place.
Where to find Warzone Haunted Hollow Mystery Box

Watch for the Ghost Train circling Haunted Hollow at the beginning of the match. Before activation it appears as a glowing, spectral train. Find a train signal along its route and interact with the signal before the train reaches it.
Activating the signal causes the Ghost Train to stop and phase into reality. When that happens, Warzone Haunted Hollow Mystery Box becomes accessible on the train alongside Supply Boxes, a Buy Station and other loot.
The Mystery Box is also marked by a beam in the sky and a Tac Map icon once the train is active. Use those indicators if another squad has already triggered the event and you are trying to locate the stopped train quickly.
How to use the Mystery Box
Interact with Warzone Haunted Hollow Mystery Box to roll for a powerful reward. The result appears for you to claim, but it does not remain there indefinitely. Take the item before it disappears.
If you do not want the item, melee it. Activision specifically confirms that meleeing the result rejects it quickly and lets you spin again. That is faster than standing around deciding while the materialised train timer continues to run.
Because the train eventually phases out again, prioritize the Mystery Box, Buy Station and Supply Boxes you actually need. The activity is deliberately time limited once the train becomes solid.
Why the Mystery Box is missing
If Warzone Haunted Hollow Mystery Box is not available, the most common reason is that the Ghost Train has not been phased into reality. A spectral train cannot be looted normally. Get ahead of it and activate a signal early enough to stop it.
If the train passes the signal without stopping, move to another signal farther along its route and trigger it sooner. The activation needs enough distance for the stop to occur.
Also make sure you are in a Haunted Hollow playlist where the seasonal map features are active. The Mystery Box described here belongs to the Haunted Hollow Ghost Train system.
Is the Mystery Box worth contesting?
Warzone Haunted Hollow Mystery Box can produce powerful loot, but the Ghost Train is visible and predictable enough to attract other squads. Treat the activation as a contested event rather than a free resupply.
Arrive with plates and ammunition if possible, clear obvious angles before spending time rolling, and avoid repeated rerolls while enemies are pushing the train. A good box result is not useful if you are eliminated before you can leave.
The Buy Station on the materialised train can be just as valuable if you already have strong weapons and need utility instead. Decide what your squad is missing before committing the whole activation window to random rolls.
How this fits the Haunted Hollow loot route
Warzone Haunted Hollow Mystery Box is one of several map-specific interactions. Trick or Treat Pumpkins around shopfronts can give powerups, the Mansion creates a low-gravity zone and the Floating Island contains the Eldritch Gate used by the Crimson Crawler secret.
That means the Ghost Train should usually be part of a route rather than the only objective in your match. If the train is on the opposite side of the map, looting pumpkins or rotating through another Haunted Hollow mechanic can be more efficient than chasing it through multiple squads.
Warzone Haunted Hollow Mystery Box is still the clearest way to get a Zombies-style random weapon roll in the seasonal map. Stop the Ghost Train, use the visible beam and map icon, roll quickly, melee unwanted results and leave before the train returns to its ghost state.
Activision confirms the Ghost Train signal, Tac Map marker, item rejection and Warzone Haunted Hollow Mystery Box behavior in the official Season 6 Warzone patch notes.
