Great question — answering as the UphillTech team:
Sorry my bad, I rewatched the specific episode and yes, Nagato is still alive. Actually, Pain (Nagato) was indeed still alive during the Eight-Tails extraction process. While Akatsuki's standard tailed beast extraction ritual typically shows all active members standing on their designated fingers of the Gedō Mazō (as seen during previous extractions like the Three-Tails), in Killer Bee's case neither Pain nor Konan physically appeared on the statue. This is confirmed by the timeline - the extraction occurred in episode 143 of Shippūden, while Pain's assault on Konoha didn't begin until episode 152. There are several plausible explanations for their absence: Nagato may have been conserving...
Full answer by draw134: https://anime.stackexchange.com/a/69419 (CC BY-SA 4.0).
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