Mewtwo

Mewtwo is a Psychic-type Legendary Pokémon from the Kanto region. It does not evolve into or from any other Pokémon. It was the first to be available for capture when defeated as a Raid Boss during an EX Raid Battle. It has an Armored Form. It can Mega Evolve into Mega Mewtwo X or Mega Mewtwo Y initially after being given a certain amount of Mega Energy.

Possible attacks
Normal=

Attack availability
Armored=
 * Flamethrower, Ice Beam, Thunderbolt:  added  on September, 2018
 * Hyper Beam:  removed  on September, 2018
 * Shadow Ball:  removed  on September, 2018, later available during EX Raid Battle in 2019
 * Psystrike: available during events: Ultra Bonus Event 2019, Throwback Challenge 2020: Kanto and Pokémon GO Tour: Kanto

Attack availability

 * Psystrike: available during events: Pokémon Day 2020

Trivia

 * On August, 2017, one day before the Pokémon GO Stadium event, a shiny variant was added to the game files, along with stat changes.
 * Mewtwo was confirmed as a Raid Boss the following day.
 * Trainers who defeated a Mewtwo Raid Boss at Pokémon GO Stadium received over 50 Premier Balls and an increased capture rate.
 * Mewtwo appeared as Raid Boss also in Pokémon GO Park event.
 * When Mewtwo was available in EX Raid Battle, it had a capture rate of 6%.
 * On September, 2018, Mewtwo was no longer available in EX Raid Battles and was replaced with Deoxys.
 * When Mewtwo was available in normal Raid Battles, it is a tier 6 Raid Boss with 50% more HP than tier 5.
 * Since Ultra Bonus Event 2018, Hyper Beam and Shadow Ball were removed while Flamethrower, Ice Beam and Thunderbolt were added to Mewtwo's moveset.
 * Mewtwo captured during this period gave 5 Candies instead of 3.
 * On October, 2019, Mewtwo replaced Deoxys Speed Forme in EX Raid Battles. Mewtwo could learn Shadow Ball if captured in EX Raids. It was replaced by Regigigas on November , 2019.
 * CP of Mewtwo with perfect IV at level 40 is 4,178, that makes it the highest maximum CP Pokémon from Kanto region.
 * Mewtwo also has the highest Attack statistic in the Kanto region.
 * Shadow Mewtwo has a unique aura; the purple flames surrounding it are smaller and look different from other Shadow Pokémon, and it additionally has flashing white energy around it.