"Many players of Dwarf Fortress have stories of dwarf colonists that have gone mad"
PG:
Some even start murderous rampages, completely emptying out a fortress that took weeks or months to build up. Sometimes, the only solution for dealing with a mad dwarf is to wall them in and hope they don’t find a way out of their cell. There’s even a very popular mod, called Dwarf Therapist that, at least the last time I got deep into the game, was considered an essential add-on.
There have been similar issues reported by the community of players that enjoy RimWorld.
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What makes the conversation among players so disturbing is that instead of imprisoning a mad, homicidal dwarf, RimWorld’s players are openly discussing executing homosexuals.