The beautiful inverted-funnel dwarven city at the heart of the ninth floor — flooded by Carl's Gate with water, bombs, and sharks to gut the faction-war economy.
Larracos is the ninth floor's central marvel — an inverted funnel of museums, colleges, theaters, temples, and living NPCs built by the Semeru dwarves reaching toward the Celestials below (an act that awakened Scolopendra at the volcano's base), its lower pleasure districts holding the Desperado Club, the mercenary and gear markets, and the faction armies. Carl weaponizes it from a floor away: opening the Gate of the Feral Gods inside the faction market, he floods the inverted cone with seawater, timed bombs, sharks, and pain-amplifier jellyfish. In twenty minutes half the city drowns — leveling the markets, killing the merchant NPCs (who cannot be replaced once a level is made), scattering shopkeepers and mercenaries, and cutting Desperado access — devastating the sponsors' ability to outfit their faction-wars armies.
Juice Box rides the Gate through to hide there and awaken her people. Only the upper NPC-residence levels are spared.
An inverted cone of tiered dwarven districts — galleries, colleges, theaters, temples — descending to an inverted castle at the volcano's base; now catastrophically flooded through its lower market levels, choked with sharks and wreckage.
The ninth-floor faction-wars city, flooded by Carl to wreck the war economy.
Also appears in books you've already read — spoiler-safe to their endings: