Once Team Aqua had arrived to find the Blue Orb in a cave on Dewford Island, Tabitha had Mightyena launch Shadow Ball to attack them, but Shelly's Carvanha deflected the attack with Hydro Pump. Once both teams realized there was nothing inside the cave, they both called their Pokémon back and retreated.
Once Tabitha and two of the grunts managed to snatch a black stone from Captain Stern, Mightyena used Shadow Ball to distract Captain Stern, while the rest went out of the building. Outside, they faced Team Rocket, who sent Seviper and Cacnea. Mightyena dodged Seviper's Poison Tail and hit it with Tackle, then used Double Team to evade Cacnea's Pin Missile. Attacking with Iron Tail, Tabitha's Mightyena blasted off Team Rocket. Just then, Ash, Max, Stern and Marius arrived. Stern sent Sealeo, whose Aurora Beam caused Mightyena to land on Tabitha, causing him to drop the suitcase containing the black stone. The other two grunts sent Mightyena as well to battle Ash's Corphish and Pikachu. The three Mightyena launched Hyper Beam, but were countered by Pikachu's Thunderbolt, Corphish's Bubble Beam and Sealeo's Aurora Beam. Seeing Max and Marius were going to report the crime to the police, Tabitha's Mightyena used Shadow Ball on them, but missed. Ash tried to run off with the suitcase, but was hit by Mightyena, causing him to drop the suitcase, whose stone was split in two pieces. Mightyena took the larger piece and gave it to Tabitha. With the stone in their possession, Tabitha and the grunts called Mightyena back and flew off.