Seadra

Biology
Seadra is known to have gene that doesn't share with its unevolved form Horsea.

Misty's Seadra

 * Main Article: Misty → At Trial Site

Seadra debuts in when  tries to complete the trial of Cerulean Gym requested by Misty in order to have a Pokémon Battle. He is in charge of battling the trainers who goes through the trial. He battles and comes close to win when he fires Hydro Pump on him. But Pidgey's evolution turns things around. With his newly learned move Wing Attack, Seadra can't keep it going for much longer and faints, letting Redwald and Pidgeotto complete the trial.