Monsterpedia Supplemental :

  Monster Aggression

  Monsters are drawn to attack humans, especially unmerged humans. If they just threw themselves against humanity's defenses that would be annoying but easily handled. However instead the aggression of monsters seems to be affected by a number of factors. First, how many humans are in the area. Second, how many monsters there are in the labyrinth. And lastly, how many monsters are present above the labyrinths. These factors not only affect how aggressive monsters are, but the formation rate of monsters within the labyrinth.

  These three factors mean that monsters tend to only become seriously aggressive when they have a strong chance of breaking out, and rapidly increase their aggression when a city's defenses start to fail. Without strong response towards monster aggression, the situation can quickly spiral out of control.

  The current situation is represented by several different levels, each indicating a bigger disaster and threat.

  Situation : Safe

  No monsters aboveground. This is what cities aim for. It's also unreachable. Even ignoring monster tamers and farms, some monsters just naturally form in high magic areas. Sewers are a common problem. Sure a random sewer goblin is likely to be eaten by the perfectly mundane rats, but you should never assume somewhere is completely free of monsters.

  Situation : Random Monsters

  The average situation for most areas. For a village this can be very dangerous, as a wandering giant or three can cause a massive amount of damage. But in a city this simply means you have to keep an eye out in deserted areas or late at night. The same precautions you need to take to avoid thieves and other unsavory humans. The most important thing is teaching children about monsters early in life so they won't be surprised. The bustle of a city won't magically keep the outside world away.

  Situation : Outbreak

  Outbreaks are when a number of monsters are free and attacking citizens. This can be a horde that broke into the city, or a group of monsters that was brought in illegally and freed. Technically a pack of goblins or orcs would count as an Outbreak, but fate is rarely that kind. Most modern outbreaks have included multiple creatures and caused several deaths. (With the singular exception of the Great Slime Outbreak in Whale Bay.)

  Outbreaks usually require delvers and other powerful fighters to hunt down and kill all the monsters on the streets. The majority of their targets will be found and eliminated easily, but it's nearly impossible to catch all monsters. Expect random dangers for the next week.

  During an Outbreak the streets are all dangerous. Even if there's been no reports of flying monsters, it's very possible some were missed. Or that scouts from the main group escaped whatever security you've put up. The best plan during an outbreak is to gather with your neighbors and defend yourselves as a group.

  Situation : Rampage

  If monsters manage to take control of the entry point for a labyrinth. Once that happens there's an unlimited supply of monsters capable of reinforcing the hordes inside the city. Those monsters may or may not work as a team, but they're drawn to attack humans, and break open other labyrinths.

  The only way to stop a Rampage is to contain the labyrinths again and establish control via teams of delvers and guards. Almost every delver's guild demands their members help put down a Rampage for the good of the city.

  Situation : Collapse

  If enough monsters get to the surface and lay claim to an area it's possible that the land will become oversaturated with mana and souls. When that happens the location collapses into the earth forming a new Labyrinth. During the Fall repeated Collapses were responsible for the majority of Labyrinths in our area. If a Rampage gets out of control an entire city can be lost to Collapses.

  Humans caught in a collapse almost certainly die. Some have survived due to random chance and fleeing the area, but that's pure gamble. No matter your skill, if the labyrinth decides to fuse you with stone you're dead. Get away from places about to Collapse. Work on keeping that disaster contained. If you can.