Yes.
>In Trainer Tower in Pokémon FireRed and LeafGreen there are three Trainers which have Shiny Pokémon. In the Single Battle mode, the seventh Trainer has a Shiny Meowth, while in Double Battle mode, the first pair of Trainers have a Shiny Espeon. Finally, in the knockout mode, the fourth Trainer will send out a Shiny Seaking.
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