Cameos: The Armored Episodes
In the lead up to the first Pokémon movie, Mewtwo Strikes Back, Mewtwo played a role in the anime itself. Over a span of three episodes, we see a mysterious armor-clad form with cold glowing eyes mercilessly act as Giovanni's unstoppable weapon, his rarest and most prized Pokémon, before this supposedly evil creature destroys the Team Rocket Headquarters and flies away without any further explanation. It was not until the movie when fans discovered this Pokémon's true identity and the lengths he would go for revenge.
Episode 63: Battle of the Badge
This episode heavily foreshadowed The First Movie, showing Gary and Ash's attempts to win the Earth Badge, with Giovanni, the Viridian Gym leader, still in possession of his prized super-clone. Gary had the misfortune of facing the unidentifiable armor-clad Mewtwo, losing in seconds, and blacking out (along with his entire cheer-leading squad).
This dialogue marks the first efforts of 4Kids to turn Mewtwo into a flat, unsympathetic, and eeeevil character, no matter how forced it is. The anime had previously made the point that there really is no such thing as an evil Pokémon -- Pokémon merely want to make their trainer happy. No, let's not wonder if Mewtwo is brutal because of a tragic past, or because of the influence of his heartless trainer. No, "there's something different about this one," Mewtwo's "not just powerful, it's evil." Gary can't accept his loss to the point of claiming that Mewtwo must be cloaked in the evil power of Satan to have been able to have defeated him, ooo. What a sore loser, Gary.
I knew this dialogue obviously wasn't what was said in Japanese, but had no way of knowing what otherwise was being said. Thanks to Dogasu's Backpack for revealing the mystery to me: Shigeru and Satoshi merely talk about how the mysterious Pokémon was so strong that his Pokémon "couldn't do a thing against it."
Anyway, after Gary's complete annihilation, Ash goes in to attempt to win an Earth Badge. Unlike Gary, Ash has the stupid dumb luck of not entering the gym until after Giovanni and Mewtwo leave on some urgent Team Rocket business, so the twerp simply needs to battle Jessie and James to earn his badge. Like Ash hasn't already beaten them like sixty times before. Gary watches in disbelief (probably at how unfair this all is).
This episode also reveals that Giovanni has a portrait of Mewtwo's sprite in his office. It appears in both Team Rocket's daydream of delivering stolen Pokemon to the boss, as well as in real life when Jessie and James do manage to bring Giovanni Misty's Togepi (which doesn't go over well).
Episode 64: It's Mr. Mime Time
During this episode, Giovanni is still away on official business. Jessie, James, and Meowth contact the boss at a Team Rocket outpost via giant-screen webcam, groveling for forgiveness, since they managed to blow up the Viridian City Gym (well, technically it was Togepi's fault). Their call appears to have interrupted his latest ego-stroking session with Mewtwo (visible behind him in the video feed), and he snaps that he wants rare Pokémon, not excuses. After hanging up on them, he turns to Mewtwo and continues in a self-congratulatory tone, "They can search the entire universe, but they'll never find a Pokémon as rare as you" (which is pretty ironic, given how often Jessie and James end up palling around with Mew, Mewtwo, and other legendaries...).
Episode 67: Showdown at the Po-ké Corral
Early in this episode, Jessie, James, and Meowth approach Team Rocket headquarters to report on their chronic failure to capture any Pokémon. As they gaze up at the impressive building, they lose their nerve and start to run away, but suddenly the entire headquarters explodes! The three of them glimpse the blue streak of Mewtwo flying away from the destruction, shedding his armor as he zooms away.
As the Team Rocket trio cautiously approaches the smoldering wreckage of what used to be their headquarters, they wonder if their boss, er, had his final blast off. But, miraculously, he and Persian climb out of the rubble completely unscathed (Persian actually looks happy, even with the circumstances). Giovanni is too distracted with obviously bigger issues to yell at Jessie and James too much, which they mistakenly and egotistically take as as vote of confidence in their abilities.