>After Suicune has been caught in the Tin Tower, he returns to his hometown, Celadon City, and can be found in Celadon Pokémon Center waiting for the player to catch all three legendary beasts. After this is accomplished, Eusine will return to the Tin Tower and wait for the player to summon Ho-Oh.
He doesn't leave, he stays in the Pokemon Center until you catch all three roaming dogs of Johto.
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