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Kobolds present another difficulty spike for dungeon explorers.
They live near volcanoes or anywhere that has high temperatures. They despise cold environments and would be weakened in them. Because of this, the biomes that spawn in stages 16 to 20 will be near or inside volcanoes. It's very rare that it'll be a desert.
No explanation was needed as to why this adds to the difficulty of clearing the dungeons.
The orc swamps might be disgusting, sure, but being inside active volacanoes was far more dangerous than wading through swamps.
Yes, the volcanoes can erupt while the party is inside. There were many instances where parties were wiped out by the unexpected eruption. It doesn't happen often, but it does happen, and that is enough.
