Growing creatures are unable to mature while hidden. Even if an egg has enough views to hatch, it will remain an egg until it is removed from the fog. Hatchlings may reach their second stage while fogged, but they cannot become adults until they are unhidden.
While it is hidden in the fog, the owner of the creature can view its lineage but other users cannot. Most actions and Breed Specific Actions cannot be performed on a hidden creature. However, hiding does not keep an egg safe from the effects of Earthquake, and hidden eggs may still be Warded to prevent death from sickness. Eggs and hatchlings currently being Teleported cannot be hidden unless the teleport is cancelled.
When the player hides an egg or hatchling, this message is displayed:
When the player unhides the egg or hatchling, this message is displayed:
Only the owner can see the dragon's info page while it is hidden. Other users will see:
When the owner views the dragon's view or lineage page while it is hidden, the owner will see:
When something is hidden, its usual sprite will be temporarily changed to a large mass of gray fog. Eggs and hatchlings with the fog sprite are often called "fogballs" by users.
- The Glitch Dragon shares the same sprite as a hidden creature.
- There was once a glitch where the egg of a Nocturne Dragon showed up as fog on an incubator.
- Fogging was originally thought of as a concept BSA for Storm Dragons to combat Dragon Sickness.
- A hidden creature's time until death is occasionally extended, with its timer showing "0 days". Normally, an egg/hatchling's time is rounded up, so one with 0 days and no hours should have died.
- On August 13, 2015, the hide/unhide action messages were changed. Previously, the action messages read:
- "You hide the egg/hatchling in a thick cloud of fog."
- "You dispel the fog around the egg/hatchling."