Wartortle has two evolutions. The first occurs at level 36 when it evolves into Blastoise. The second happens when a player uses an item called a Mega Stone while in battle, at which point Blastoise evolves into Mega Blastoise.
One can get a Wartortle either by capturing one in the friend safari in "Pokémon X" or "Pokémon Y" or by evolving a Squirtle. Squirtle evolves into Wartortle at level 16. Throughout all stages of its evolution, it keeps its water type, which gives it access to many water-based attacks and abilities. It also has the innate ability called "Torrent," which boosts the damage of water-type attacks when its HP falls below 30 percent of its maximum.