Name a geological period: rare answers

There are 22 correct answers to “Name a geological period” on our list. The obvious ones, like Cretaceous, Jurassic and Triassic, are worth 10 points each; the rare ones, like Statherian, Orosirian and Rhyacian, are worth far more.

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The rarest answers

This list has no Abyssal tier, so the Midnight Zone is as deep as it goes: Statherian, Orosirian, Rhyacian, Ectasian and Calymmian, worth 85 points each.

Rarity tiers are our own estimate of how few people would think of each answer. For strategy, read how to find One in a Krillion answers.

Guides for prompts like this

• Think past the first answer

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