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Tier 3 raid boss list
The announcement mentioned Aerodactyl, but I guess Omastar, Kabutops and Onix may also return for the event? During the Kanto event, I finally managed to solo Omastar, but did not spot any Aerodactyl raids.
(Bonus question: What do you think the Tier 3 raid lineup will be after the Lati twins leave? Granbull and Pinsir are likely to be removed, but will Jynx still be around?)