Episode AppearanceHere is the summary and a small row of screenshots that Zapdos appears in.
Season 5 - Episode 242: As Clear as Crystal
Ep 244: Thunder and the Crystal! Secret of the Lake!
After Pikachu is weakened by a run in with Team Rocket, a woman knows of a secret place to heal the electric mouse. Ash and the gang see some electric Pokemon walking the same decoration as they're going. They follow the woman to a lake which has a crystal capable of healing electric Pokemon. Ash puts Pikachu into the lake and it quickly heals. Team Rocket over hears about the legendary crystal and steals it. The electric Pokemon and Pikachu get mad at them and try to save the object by using their electric attacks on them but the evil team uses their latest machine to absorb their attacks! Then an angry figure appears in the sky and uses an electric attack to stop their electricity from being absorbed. A thunder storm appears and the legendary Pokemon, Zapdos appears from beneath the dark clouds and uses an electric attack the evil team, which ends up being absorbed by the machine as the lightning bird starts to get weak. With encouragement from the woman, the yellow bird strengths it's attack, which blasts off Team Rocket. Using too much of it's electricity, it falls to the ground. Being scared of the woman, it uses more of it's electricity and faints. The woman tells Ash and the gang that normally the machine wouldn't effect Zapdos. Brock guesses that the electric type Pokemon must have come to get healed by the legendary crystal which happens to be correct. With the crystal gone, the lake can no longer heal Zapdos or any other electric Pokemon. Ash and the gang go to retrieve the crystal from the evil team, which takes a while but they finally get the crystal back. Ash puts the object back into its place but it's not glowing, Pikachu and the electric Pokemon use their electric attacks to make the crystal glow again. They put Zapdos into the lake but the object stops glowing but the Pokemon use their attacks on the crystal and on Zapdos, which heals the electric bird as Zapdos then recharges the crystal with it's attack. Then the lightning bird leaves as the dark clouds start to drift away.
Season 19 - Episode 905: An Electrifying Rage!
Ep 911: Thunder and Onvern! The Angry Lightning Strike!!
Cilan becomes excited despite the fact that he usually doesn't behave this way, he tells Ash and the rest of the gang that they're going to an electric type celebration which is a festival that features Zapdos. He tells the a story about how a tree in the center of Jewel town was split by a bolt of lightning that was caused by Zapdos but surprisingly it grew back, becoming bigger and stronger and grew berries. Since the town's people where very thankful of what Zapdos did, they created the festival. By doing so, they hoped that the electric Pokemon will appear once more and bring the town good luck. Bonnie asks what is a Zapdos. He explains that it's a powerful Pokemon that can control lightning and talks about the other two Legendary Birds and how the three of them make a powerful trio. Then a bolt of lightning appears near by and then the electric bird itself appears, which amazes the gang but Cilan realizes that if they don't get to the festival, then they'll miss the main event. Suddenly a strike of lightning makes a tree collapse very close to the electric type trainer. Since it's too dangerous, they take shelter in a cave, in the cave they encounter a paramedic who's leg is injured and can't deliver medicine to a sick child in town, the gang agrees to help him but the path way that leads straight to Jewel Town is blocked. It's no problem for Ash as him and the gang walk through the cave, as Team Rocket is trying to capture the legendary Pokemon and because of them a rock slide separates Ash from his friends. As Ash goes alone with his Pokemon and Noibat finds a tunnel which leads them to Zapdos, then finds Team Rocket. With Ash wanting to find out what's going on, Meowth explains they tried capturing Zapdos but failed, which is why the electric Pokemon is angry. Ash tries to reason with it but it doesn't work, he distracts it by letting his Pokemon battle it. When Hawlucha is defeated, Noibat evolves and battles the legendary bird and weakens Zapdos but then Team Rocket tries to capture the Pokemon yet again since it's weakened and succeed. Noivern frees the yellow and black bird, upon freeing it, Zapdos decides to let them pass as the dark clouds turn back to normal and the bird leaves. In town as a fireworks display begins, they see the electric bird flying as it uses an electric attack among the fireworks and leaves.