“Bio warfare” describes a digital rhetorical tactic used by teen climate activist Greta Thunberg to challenge oppressive anger norms and assert a feminist paradigm that sees sometimes-angry teen girl activists as credible, rational rhetors. On the surface, the rhetorical strategy is simple: Thunberg copy/pastes world leaders’ disparaging language into her 160-character Twitter bio. Yet, in these seemingly simple Twitter bio updates, Thunberg recontextualizes conservative leaders’ language into her own Twitter profile, inverting their meaning to assert an opposing ideology: that teen girls’ anger can be wise.