Latios can Mega Evolve into Mega Latios if it is holding a Latiosite.
Mega Latios is a part of the Overused (OU) tier of competitive battling. While its base form is quite capable on its own, Mega Latios is a very legitimate threat in OU due to its higher Attack stat and better overall bulk. Thanks to a base 130 Attack, Mega Latios can utilize Earthquake to hit the likes of Tyranitar, Heatran and Assault Vest Magearna, all of which are typical answers to base form Latios. Mega Latios is also far less susceptible to Knock Off in comparison to its base form, and it is better overall at taking hits. A typical Mega Latios set consists of its STAB attacks Draco Meteor and Psychic to dish out significant damage alongside Earthquake for coverage and Roost to help with longevity. While Mega Latios is a very good Pokémon, it has issues with Fairy-types like Tapu Lele as well as Steel-types such as Celesteela, Ferrothorn, and Mega Scizor. That said, it is a strong wallbreaker that can get past conventional Latios checks and allow for other Pokémon to take full advantage, making it a solid Pokémon in the tier.
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