40d:Tantrum

Dwarves are fickle creatures, and when pressed to the breaking point of their happiness, they will tantrum. A tantruming dwarf may attack people and animals, destroy buildings, or throw things. The dwarf will receive happy thoughts from doing this. Those acts are generally considered a crime.

Dwarves will tantrum if they are at the "very unhappy" level of happiness or worse. If a dwarf has created a masterpiece-level item, they will also throw a tantrum if it rots, or is ever destroyed or stolen. Masterpiece engravings can be destroyed by miners digging out walls or floors.

However, dwarves will not tantrum if a masterpiece building is dismantled.

It is not impossible for a tantruming dwarf to destroy the bridge they are standing on and drown.

Tantrum chains

If any dwarf throws a tantrum in the beginning of the fortress's life, it should be taken as a warning. When this happens, it often signifies that the other dwarves are unhappy--and if they aren't already, they probably will be soon.

In more mature fortresses, tantrums have been known to have similarly nasty results. In one extreme case, a chain of tantrums was observed which eventually brought the fortress to its metaphorical knees. Chains don't occur particularly often, but when they do, they are extraordinarily hard to stop.

They generally play out something like this:

Dwarf A throws a tantrum, and punches Dwarf B. A recovers happily, but B throws a tantrum and smashes the butcher's workshop to bits. The butcher, C, tantrums and destroys the table of the closest noble, D. D tantrums, starting fights with three other dwarves--A, C, and E. All of them tantrum, and C is taken into custody. E gets busy and smacks B. Meanwhile, C is killed by the hammerdwarf, accidentally or otherwise. C's friends, F, G, H, I, J, and K, all tantrum and do other nasty things. Everybody eventually tantrums and the fortress production grinds to a halt. Everybody starves, throws themselves into a volcano, or otherwise dies.

• Ways to check dwarfs's happiness