Dialga

Dialga, while not as good a wallbreaker as Mega Diancie or Mega Rayquaza, has quite a few distinct properties that make it good in the Balanced Hackmons metagame. Its unique Steel / Dragon typing provides a resistance to Flying and a neutrality to Fairy, corresponding to two of the more commonly used -ate abilities in Aerilate and Pixilate. Steel / Dragon is an interesting offensive typing as well, giving it unresisted coverage with just Tinted Lens and its STAB moves, with Dragon alone being unresisted itself outside of Fairy-types. Tinted Lens allows Dialga to lure in and deal massive damage to Steel-types such as Registeel and Aegislash, which rely on their resistances to take hits. Its bulk is decent, and its Special Attack is quite good, but it is a bit on the slow side. Pokemon with Imposter present a problem to it, requiring a Fairy-type Pokemon with Magnet Pull and Substitute to be dealt with reliably. Overall, Dialga is a massive threat when set up and can sweep unprepared teams with ease.