Escavalier is a Bug/Steel Pokémon introduced in Generation 5. It's the evolved form of Karrablast, and the method in which it evolves also causes Shelmet to evolve into Accelgor. If either Pokémon holds an Everstone, neither evolves.
All canon Pokémon are available in Tropes vs. Women in Pokémon Training, including Escavalier; however, it can't be found in the wild. It's mostly unchanged from canon in that game.