Reference · Book 1, Dungeon Crawler Carl
The Black Death and the great gerbil
Real epidemiological revision (Schmid et al., 2015) proposing that Asian great gerbils rather than black rats carried plague along the Silk Road into fourteenth-century Europe — recited by the System AI as the backstory for Ralph, a fictional level-11 boss who thinks 200 million dead is too few.
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The AI's history lesson before Ralph (ch. 45) reflects a real 2015 revision of plague epidemiology; the fictional gerbil's grievance is that 200 million was too few.