A second-floor incident bad enough that three crawlers chose their entire classes around never being burned by acid again.
When Carl notices that Li Jun, Li Na and Zhang all shrug off the acid blood of the Krakaren Juvenile Cloneling, he learns why: after the incident with the Brindle Grubs on the second floor, acid immunity was something all three deliberately looked for in their respective classes. He does not blame them. It is the clearest example yet of crawlers building their characters around a trauma rather than a strategy.
The second-floor monster whose acid shaped three crawlers' entire builds.
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