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Sources — 4 recorded facts, by chapter
Chapter 44
- Reaching the halfway point of the level lets game guides explain the third floor and the race/class selection process.
- The third floor is an 'over city,' and every third floor (third, sixth, ninth, twelfth, fifteenth, eighteenth) shares the same setting and comes into existence simultaneously.
Chapter 48
- The third floor is described as an all-important floor where finding stairwells will not be a problem, unlike later floors.
- Crawlers select a new class and race upon reaching the third floor.