Maybe something that like Gastrodon that has Storm Drain as an ability? All water type moves (except Surf) are Drawn to him. A good Electric type alternative would be a Pokemon with Lightning Rod as an ability. Like Surf, Discharge can still hurt Charizard, however. Swampert, Garchomp, Steelix, and Quagsire are also all pretty good candidates.
Be warned single Pokemon won't be able to cover all of the types though.