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Tear Jerker: Robopocalypse
The North Star drilling team, who unknowingly installed Archos into its location in remote Alaska. The team lost one member during the process, with the rest slowly dying of radiation poisoning due to the location being the site of a nuclear bomb explosion.
The end of Laura Perez's story, also. Though her children are able to escape (and later help the war against Rob), there is no further mention of her.