Lately, I have been playing with the mausritter world building tools. Here is something that I might use in a future oneshot.

The setting

The basic idea is that the home settlement is located in a small village in a radioactive area. More precisely, it is on top of an old carousel under the tent-like structure. For an unspecified reason the structure is protecting the mice. They call it the arch.

Going outside is dangerous but necessary to retrieve food and water. Small parties called spotters are going around looking for loot. Once a source has been located, a caravan is sent there using the shortest and most efficient path possible. Those who stay outside for too long fall victim of the curse. They get sicker and sicker until die in great suffering.

The leader of the settlement is the head of a cult dedicated to the horse statues that compose the carousel. They are viewed as the guardians of the settlement. Rituals are performed in their names. Anyone who deviates from the traditions risks angering the guardian.

The non-believers are the biggest group in the settlement but keep a low profile because they don't want to be cast out. Many mice are discussing what protections are effective against the curse. Every mouse has its own probably incorrect solution: eating dirt, painting one's ears in red, etc. A few old mice have known the blessed era when they would mostly live outside. Humans used to be there too and those where sometimes dangerous. Freedom was worth this price.

Most mice believe that the curse is a global phenomenon. Parties have been sent away but since the curse takes a few weeks to reveal its effects no one is sure if things are safer elsewhere. Some mice called the escapists think that the phenomenon is local, although they disagree how large is the affected area. If anyone is caught publicly discussing this topic he is immediately accused of heresy and risks being cast out of the arch ("leave now if you so dearly wish so!").

How to run the setting

PCs take the role of a fresh group of spotters. They need to go outside to find food. This is the basic structure of the session: go outside to spot some fruits, grains or seeds. Then things happen and the player must react.

Examples of basic events:

• A dying animal comes in the area. His fur and his meat are highly valuable. The PCs have to stalk it and possibly kill it.
• an unknown mice party wears strange clothes. They look older than most spotters from the arch meaning that they may have found an effective protection.
• a caravan got lost. He has found some strange device emitting noise. Its noise seems to be linked to the intensity of the curse.

More involved:

• a cat is around. He helps the player to find a decent source of food. He pretends that a group of rats is keeping a cure for the curse to themselves. The rats have offended the cat. The cure is a lie to punish the rats. Convert an existing dungeon to represent the rats camp.
• two escapists want to join the PCs to start an expedition. In exchange for guiding them outside of town the escapist will reveal the location of a valuable treasure. PCs should be careful not to be seen with those escapists.