Kill them all!

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Henzell says...

A vault on its own separate map/maps, entered through a portal (same symbol as e.g. the Hell entrance). Portal vaults include gauntlets, bazaars, treasure troves, ziggurats, sewers, ossuaries, baileys, ice caves, volcanoes, and wizlabs. Each vault type has its own entry in the learndb; see it for details.

Information based on master branch and the great LearnDB.
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