" Thirteen " is a pivotal episode of The 100 that bridge's the series' Grounder mythology with its hard science-fiction origins. It is widely regarded as the most controversial hour in the show's history due to the death of a major character. Executive Summary
: Becca, an elite scientist, created A.L.I.E. 1.0, which subsequently triggered the nuclear apocalypse to "solve" overpopulation. [S3E7] Thirteen
: To prevent the AI from "infecting" the other 12 stations (which became the Ark), the Ark commanders ordered Polaris destroyed. " Thirteen " is a pivotal episode of