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What type of bug are you reporting? Unsure
What is the bug?
https://replay.pokemonshowdown.com/gen9fortemons-2025618537-o0u5rtsj5xdqoo4rsuek7cnu3ib59jppw [Turn 7 onwards]
Terapagos-Stellar's model has some weird interactions with Substitute/Shed Tail
Are you able to replicate it? If so...