Pokemon the Series: Ruby & Sapphire Season 602 Episode 6 Sharpedo Attack!

On their way to Dewford Island on Briney's boat, Ash and friends make a stop at a beautiful bay for some swimming when they're boxed in by a huge school of Sharpedo. Brock is puzzled because Sharpedo normally travel alone. One of the Sharpedo seems to be the leader, and Brock thinks that if our heroes can defeat that one in battle, the others will stand down. But when the battle begins, Sharpedo collapses from poison immediately! Brock spends all day and night caring for the sick Sharpedo. The next morning, Team Rocket shows up and reveals that it was Seviper's Poison Tail attack that poisoned the boss Sharpedo. The Sharpedo gang chases off Team Rocket and befriends Ash and company.