Mega Swampert

Mega Swampert runs Torrent instead of Damp because the team sometimes fields both Beedrill and Swampert without mega evolving Swampert, so a damage focused ability matters more than a safeguard against Explosion. Adamant nature with maxed Attack and Speed lets Swift Swim carry it past threats like Mega Aerodactyl once it evolves, and Wave Crash hits harder still under the team's own rain. Rock Slide pressures Charizard without forcing a switch, while High Horsepower stays single target since only Pelipper is immune to Ground moves and a spread Earthquake would risk clipping an ally. Protect buys time to reposition.