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Olm

Proteus anguinus · impossible

The olm spends its entire life in the flooded caves of the Dinaric karst, in complete darkness, and its body is a catalogue of what that costs and what it saves. It is pale pink — unpigmented skin through which blood shows. Its eyes are undeveloped and grown over. In their place it navigates by smell, by sensitivity to water movement, and by detecting weak electric fields.

It keeps its larval form for life, retaining external gills as a permanent feature, and it grows to around twenty-five centimetres with a slender, almost snake-like body and small limbs.

What is most remarkable is its pace. Caves offer very little food, and the olm has responded by slowing everything: it can survive years without eating, moves rarely, may not breed until well into adulthood, and appears to live past a century. Individuals have been observed to sit in the same spot for years at a time.

Local folklore held that they were the young of cave dragons, washed out by floods. Their real vulnerability is water quality — the karst drains straight into the aquifers they live in, so agricultural and industrial pollution at the surface arrives underground almost unfiltered.

Where it lives

Worml lists the olm as native to 4 countries — Bosnia and Herzegovina, Croatia, Italy and Slovenia. Its habitat is flooded karst cave systems.

Ranges here are reduced to whole countries for playability and exclude introduced populations — see about the data for what that simplification leaves out.

In the game

Olm is rated impossible. To solve the round you need to find any 2 of its 4 listed countries. How scoring works →

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