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Galarian Articuno's Expanding Force was not hitting both opponent's pokemon. Psychic Terrain was up and Indeedee's Expanding Force worked just fine.
https://replay.pokemonshowdown.com/gen8vgc2021-1209351120-a623fkocd45aunuoeb2qzu9thilucgqpw
BUG STATUS: NOT A BUG, Galarian Articuno isn't...