Mewtwo
Type: Psychic
Stats: 106 | 110 | 90 | 154 | 130
Introduction
Mewtwo is the best Pokemon in RBY 1P, it's really quite that simple. The meta revolves around getting into a position for your own Mewtwo to do work, while at the same time stopping your opponent from getting their own Mewtwo going. There aren't really any Mewtwo "counters", your best bet is either crippling it via status, winning a Mewtwo freeze war, using FlashTwo, or forcing it out with Explosion threats.
Sets
Standard
Mewtwo
- Amnesia
- Recover
- Ice Beam
- Psychic
Set Details
This is the classic Mewtwo set, and the one you should prepare for in general. Ice Beam helps in the Mewtwo ditto, and leaves the loser of the freeze war basically unusable for the rest of the game. Psychic is Mewtwo's STAB and it KO's most Pokémon at 999 Special (which it reaches after 2 Amnesias!)which aren't Psychic-resistant, with the notable exception of completely healthy Snorlax. The loser of the freeze war in a good portion of games, will end up losing the game simply because Mewtwo is the most powerful piece on either side. Psychic also lets Mewtwo attempt to break some of its checks such as paralyzed Light Screen Chansey via Special drops, and turns on which Chansey gets fully paralyzed. Thunderbolt is also a valid option that lets it beat Slowbro which can otherwise go toe to toe with it, although there is opportunity cost both in dropping Psychic and in dropping Ice Beam from your set. If you were to drop Ice Beam, then that prevents you from engaging in a freeze war with other Mewtwo's which is a huge downside - but if you can let a partner, such as Light Screen Chansey, take the freeze, then this set has very few downsides - except, Exeggutor can now consistently force out Mewtwo via the threat of Explosion as it takes little from its attacks. If you were to drop Psychic, then you lose out on being able to beat Light Screen Chansey, and a relatively healthy Snorlax(as opposed to a full health Snorlax when Psychic is run) can now check Mewtwo quite nicely. Thunderbolt and Ice Beam run together, is a sort of compromise, that allows you to beat Slowbro, and Exeggutor while also being able to engage in Freeze wars with Mewtwo, but has the downsides as listed, making it generally weaker and slightly less capable as a cleaner.
Asd Assassin
Mewtwo
- Self-Destruct
- Amnesia
- Psychic
- Thunder Wave
Set Details
This set opts to not use Mewtwo as a win condition, instead it bluffs the standard Amnesia Mewtwo, seeking to paralyze and chip at the opposing Mewtwo before using a surprise Self-Destruct. Mewtwo's Selfdestruct does damage in the range of about 50 to 60%, so you should aim to have weakened the opposing Mewtwo to a point where Self-Destruct, if not KOing the opposing Mewtwo, at least leaves it sufficiently weakened that it's ineffective for the remainder of the match. A few things can do the job of chipping Mewtwo, such as Seismic Toss Chansey, Tauros,Snorlax,Exeggutor, Mew, and Zapdos - some of which can also paralyze Mewtwo with Thunder Wave, Stun Spore, or Body Slam, as well as possibly scaring it with Self-Destruct. By doing this you can avoid engaging in a game-deciding freeze war, and can instead look to set up the game for something else on your team(Surf Slowbro is a particularly good option) by trading Mewtwo on both sides.
Psychic is the main recommended attack because it provides a reliable STAB, as well as helping to bluff the standard set. It is generally superior to Ice Beam since it does not aim to engage in a freeze war, due to its lack of recovery, and Self-Destruct; the ability to get Special falls with Psychic is also far more useful than having a neutral attack when versus a paralyzed Mewtwo. If you can reliably paralyze Mewtwo in another way(for example with the assistance of Pokémon such as Chansey, Slowbro or Exeggutor), then dropping Thunder Wave to run Recover becomes a good option.It helps tohide the presence of Self-Destruct on Mewtwo's set, making it a more effective lure so long as the opposing Mewtwo is pre-paralyzed. The set is named after marcoasd.
HM Slave (Flashtwo / DisasterTwo)
Mewtwo
- Flash
- Amnesia
- Recover
- Psychic
Set Details
This Mewtwo should be held back until opposing Mewtwo is revealed because it specifically is meant as a primary Mewtwo answer, and has a huge advantage in a mirror match. Flashtwo can boost alongside, and then can utilise flash to make it difficult to hit, and hence even more difficult to freeze. It beats standard Mewtwo on PP, and that leaves you with a fully boosted Mewtwo with Psychic that can clean up the opposing team or at least do some damage, whilst negating the effectiveness of the opponent's Mewtwo. This set however still struggles with Slowbro, just like the standard Mewtwo set, so you should have some plan in place for dealing with Slowbro safely without using Mewtwo. Another noteworthy counter is Lutrew, which can consistently take FlashTwo on in a mirror match, if it's not forced to take on something else early on. Exeggutor also becomes a bit more of a pain, because it can just stay in and seek to cripple you with Stun Spore without too much risk, due to the absence of Ice Beam on this Mewtwo'sset, which can put Mewtwo into risky situations where it can be pressured with Pokemon such as Snorlax. This set is sometimes known as DisasterTwo since it was originally thought of by Disaster Area.
Other Options
Seismic Toss could be run over Psychic on the Asd Assassin set; 2 Seismic Tosses plus Self-Destruct KOs Mewtwo, which with the support of paralysis could work effectively, however using it gives away the surprise of the set making it an inferior option. It could also be run over Thunder Wave instead, allowing you to abuse the guarantee'd KO only if you require it, with the set still more heavily focussed on keeping Self-Destruct as a surprise. Barrier is a poorbut notable option; Barrier has more PP than than Ice Beam, so a paralyzed Barrier Mewtwo beats an opposing standard Mewtwo on PP. It also helps protect against being broken by Asd Assassin Mewtwos, Mews, Zapdos, Snorlax, and others. Submission is also another option seen at times, to help get past Chansey, but is generally an inferior option to Psychic which, when boosted by Amnesia can be used to break past Chansey, albeit at a cost of PP, whilst being useful for a number of other reasons. Finally, Counter is noteworthy because of its flexibility, but it's not particularly useful on Mewtwo compared to its other options, however it definitely has validity and a strategy could be built around it.
Checks and Counters
There's a number of ways to take on Mewtwo, some of which are more effective than others. To some extent it depends on what set Mewtwo is running as to what's an effective answer: for example, if Mewtwo isn't running Thunderbolt then Slowbro makes a great answer, alongside your own Mewtwo, but if it it's running Thunderbolt then it's probably not running Psychic and so Light Screen Chansey makes a good answer. You can try and take on Mewtwo with your own Mewtwo first and try to win a freeze war, if you're running standard Mewtwo, and then use something else such as your own Chansey or Slowbro to take it on should you lose it. However there's a number of other means to taking it on; alternative Mewtwo sets such as the Asd Assassin and FlashTwo can be used to either lure and explode on or PP stall Standard Mewtwo, for example. You can endeavor to paralyze it, for example with Mew, Zapdos, or Chansey, and then proceed to pressure it through the use of strong physical attackers such as Snorlax and GGMew, and through the threat of Explosion such as from Exeggutor. Lutrew can be used to effectively have a second Mewtwo, if it is in a fit state to take it on by the time Mewtwo comes out.
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Co-authored with Disaster Area.

Type: Psychic
Stats: 106 | 110 | 90 | 154 | 130
Introduction
Mewtwo is the best Pokemon in RBY 1P, it's really quite that simple. The meta revolves around getting into a position for your own Mewtwo to do work, while at the same time stopping your opponent from getting their own Mewtwo going. There aren't really any Mewtwo "counters", your best bet is either crippling it via status, winning a Mewtwo freeze war, using FlashTwo, or forcing it out with Explosion threats.
Sets
Standard
Mewtwo
- Amnesia
- Recover
- Ice Beam
- Psychic
Set Details
This is the classic Mewtwo set, and the one you should prepare for in general. Ice Beam helps in the Mewtwo ditto, and leaves the loser of the freeze war basically unusable for the rest of the game. Psychic is Mewtwo's STAB and it KO's most Pokémon at 999 Special (which it reaches after 2 Amnesias!)which aren't Psychic-resistant, with the notable exception of completely healthy Snorlax. The loser of the freeze war in a good portion of games, will end up losing the game simply because Mewtwo is the most powerful piece on either side. Psychic also lets Mewtwo attempt to break some of its checks such as paralyzed Light Screen Chansey via Special drops, and turns on which Chansey gets fully paralyzed. Thunderbolt is also a valid option that lets it beat Slowbro which can otherwise go toe to toe with it, although there is opportunity cost both in dropping Psychic and in dropping Ice Beam from your set. If you were to drop Ice Beam, then that prevents you from engaging in a freeze war with other Mewtwo's which is a huge downside - but if you can let a partner, such as Light Screen Chansey, take the freeze, then this set has very few downsides - except, Exeggutor can now consistently force out Mewtwo via the threat of Explosion as it takes little from its attacks. If you were to drop Psychic, then you lose out on being able to beat Light Screen Chansey, and a relatively healthy Snorlax(as opposed to a full health Snorlax when Psychic is run) can now check Mewtwo quite nicely. Thunderbolt and Ice Beam run together, is a sort of compromise, that allows you to beat Slowbro, and Exeggutor while also being able to engage in Freeze wars with Mewtwo, but has the downsides as listed, making it generally weaker and slightly less capable as a cleaner.
Asd Assassin
Mewtwo
- Self-Destruct
- Amnesia
- Psychic
- Thunder Wave
Set Details
This set opts to not use Mewtwo as a win condition, instead it bluffs the standard Amnesia Mewtwo, seeking to paralyze and chip at the opposing Mewtwo before using a surprise Self-Destruct. Mewtwo's Selfdestruct does damage in the range of about 50 to 60%, so you should aim to have weakened the opposing Mewtwo to a point where Self-Destruct, if not KOing the opposing Mewtwo, at least leaves it sufficiently weakened that it's ineffective for the remainder of the match. A few things can do the job of chipping Mewtwo, such as Seismic Toss Chansey, Tauros,Snorlax,Exeggutor, Mew, and Zapdos - some of which can also paralyze Mewtwo with Thunder Wave, Stun Spore, or Body Slam, as well as possibly scaring it with Self-Destruct. By doing this you can avoid engaging in a game-deciding freeze war, and can instead look to set up the game for something else on your team(Surf Slowbro is a particularly good option) by trading Mewtwo on both sides.
Psychic is the main recommended attack because it provides a reliable STAB, as well as helping to bluff the standard set. It is generally superior to Ice Beam since it does not aim to engage in a freeze war, due to its lack of recovery, and Self-Destruct; the ability to get Special falls with Psychic is also far more useful than having a neutral attack when versus a paralyzed Mewtwo. If you can reliably paralyze Mewtwo in another way(for example with the assistance of Pokémon such as Chansey, Slowbro or Exeggutor), then dropping Thunder Wave to run Recover becomes a good option.It helps tohide the presence of Self-Destruct on Mewtwo's set, making it a more effective lure so long as the opposing Mewtwo is pre-paralyzed. The set is named after marcoasd.
HM Slave (Flashtwo / DisasterTwo)
Mewtwo
- Flash
- Amnesia
- Recover
- Psychic
Set Details
This Mewtwo should be held back until opposing Mewtwo is revealed because it specifically is meant as a primary Mewtwo answer, and has a huge advantage in a mirror match. Flashtwo can boost alongside, and then can utilise flash to make it difficult to hit, and hence even more difficult to freeze. It beats standard Mewtwo on PP, and that leaves you with a fully boosted Mewtwo with Psychic that can clean up the opposing team or at least do some damage, whilst negating the effectiveness of the opponent's Mewtwo. This set however still struggles with Slowbro, just like the standard Mewtwo set, so you should have some plan in place for dealing with Slowbro safely without using Mewtwo. Another noteworthy counter is Lutrew, which can consistently take FlashTwo on in a mirror match, if it's not forced to take on something else early on. Exeggutor also becomes a bit more of a pain, because it can just stay in and seek to cripple you with Stun Spore without too much risk, due to the absence of Ice Beam on this Mewtwo'sset, which can put Mewtwo into risky situations where it can be pressured with Pokemon such as Snorlax. This set is sometimes known as DisasterTwo since it was originally thought of by Disaster Area.
Other Options
Seismic Toss could be run over Psychic on the Asd Assassin set; 2 Seismic Tosses plus Self-Destruct KOs Mewtwo, which with the support of paralysis could work effectively, however using it gives away the surprise of the set making it an inferior option. It could also be run over Thunder Wave instead, allowing you to abuse the guarantee'd KO only if you require it, with the set still more heavily focussed on keeping Self-Destruct as a surprise. Barrier is a poorbut notable option; Barrier has more PP than than Ice Beam, so a paralyzed Barrier Mewtwo beats an opposing standard Mewtwo on PP. It also helps protect against being broken by Asd Assassin Mewtwos, Mews, Zapdos, Snorlax, and others. Submission is also another option seen at times, to help get past Chansey, but is generally an inferior option to Psychic which, when boosted by Amnesia can be used to break past Chansey, albeit at a cost of PP, whilst being useful for a number of other reasons. Finally, Counter is noteworthy because of its flexibility, but it's not particularly useful on Mewtwo compared to its other options, however it definitely has validity and a strategy could be built around it.
Checks and Counters
There's a number of ways to take on Mewtwo, some of which are more effective than others. To some extent it depends on what set Mewtwo is running as to what's an effective answer: for example, if Mewtwo isn't running Thunderbolt then Slowbro makes a great answer, alongside your own Mewtwo, but if it it's running Thunderbolt then it's probably not running Psychic and so Light Screen Chansey makes a good answer. You can try and take on Mewtwo with your own Mewtwo first and try to win a freeze war, if you're running standard Mewtwo, and then use something else such as your own Chansey or Slowbro to take it on should you lose it. However there's a number of other means to taking it on; alternative Mewtwo sets such as the Asd Assassin and FlashTwo can be used to either lure and explode on or PP stall Standard Mewtwo, for example. You can endeavor to paralyze it, for example with Mew, Zapdos, or Chansey, and then proceed to pressure it through the use of strong physical attackers such as Snorlax and GGMew, and through the threat of Explosion such as from Exeggutor. Lutrew can be used to effectively have a second Mewtwo, if it is in a fit state to take it on by the time Mewtwo comes out.
---
Co-authored with Disaster Area.