Sceptile

With its blazing Speed and relatively high Special Attack that allows it to take out the likes of Suicune, Mega Salamence, Garchomp, and Rotom-W, Mega Sceptile makes for an efficient revenge killer and late-game cleaner in the Battle Spot Singles metagame. Lightning Rod gives Mega Sceptile immunity to Electric-type moves and a Special Attack boost if it switches into one. Additionally, Mega Sceptile's resulting immunity to Thunder Wave is a huge boon for it by completely removing one of the primary methods to lower its Speed, its greatest asset. Mega Sceptile's secondary typing in Dragon is a huge benefit, as it grants it a secondary STAB type to utilize, removes its weakness to Fire, and gives it a 4x resistance to Water, improving its matchup against the likes of Heatran and Rotom-H. However, Mega Sceptile's typing also gives it a 4x weakness to Ice and new weaknesses to Dragon and Fairy. Mega Sceptile is also quite frail, and the prevalence of priority in Battle Spot Singles gives it a disadvantage against common Pokemon such as Talonflame, Kangaskhan, and Mamoswine. Although Grass / Dragon has decent coverage on its own, Mega Sceptile's STAB moves are walled by Steel-types such as Aegislash, Mega Mawile, Ferrothorn, and Heatran, making its role at cleaning teams a lot more difficult. Even with a high base Special Attack of 145, Mega Sceptile fails to beat the common walls and bulky Pokemon of Battle Spot such as Cresselia, Porygon2, and specially defensive Thundurus.