Mewtwo is approximately as dominant in Pokemon GO as in any other game in which it appears.
In terms of stats, moves and just overall performance, Mewtwo is as close to the perfect Pokemon as Niantic can get. It has an amazing 300 Attack stats, paired with powerful moves that come with lower energy costs. Ignoring PvP, Mewtwo can beat most raid bosses on his own. There is almost no “ideal” driver for Mewtwo, because there are so many great options. This is generally a good way to build Mewtwo.
What are the best moves for the most powerful Pokemon in the game?
Both of Mewtwo’s quick moves have their merits, but Confusion is generally better. Psycho Cut generates more energy than confusion, but the difference is negligible compared to the difference in damage. Confusion has a basic strength of 20, which far exceeds the strength of 5 Psycho Cut.
As for charging moves, every Mewtwo should have a STAB Psychic move and a choice of coverage. As for the psychic move, Psystrike is slightly better than Psychic, but both are acceptable.
Both of these moves require only half an energy bar and have 90 base powers. The only real difference between the moves is that Psystrike’s animation finishes a little faster, resulting in a higher DPS. Of course, EliteTMs may be scarce, and other Pokemon may need more. It is not always necessary to spend EliteTM on Mewtwo, which works well with Psychic.
Mewtwo then chooses between a handful of great moves to cover. However, from a pure damage standpoint, Shadow Ball is the preferred choice. This move has a slightly higher DPS than other options like Flamethrower, Ice Beam and Thunderbolt.
However, damage is not the only thing. Coaches also need to look at utility. What Shadow Ball allows Mewtwo to do is become a great counter to the confrontation of psychic types. In fact, many psychic types, like the Deoxys Defense Form, have Mewtwo as one of their best attack counters, simply because they can learn Shadow Ball. Mewtwo can also oppose popular Pokemon with this move, such as Metagross and Giratina.
That being said, however, there are certainly opportunities to use other moves. The icy ray is good for dealing with popular dragons like Dragonite and Rayquaza. The flame thrower can break through bulky steel types. Focus Blast, however, is a particularly nice option as it hits incredibly bulky Pokemon like Blissey and Snorlax.