Mew

A Lum Berry could be used if you want Mew to momentarily avoid status, however this seriously compromises Mew's overall staying power. Max HP EVs are used to maximize bulk and 220 Defense EVs are used to help Mew check a variety of physical threats such as Terrakion. 32 Speed EVs allow Mew to outrun max Speed Tyranitar. A Bold nature is used to further increase Mew's physical bulk, however a Calm nature with Special Defense EV investment may be used to balance Mew's defenses and let it handle both physical and special threats.

Mew has a plethora of optional moves to choose from, each useful, largely depending on your team. Aura Sphere can be used to get some good damage against Tyranitar and Steel-types, while Flamethrower lets Mew roast Steel-types, especially those that are severely weak to Fire-type moves, namely Scizor, Ferrothorn, and Forretress. Shadow Ball allows Mew to get decent damage against Latios and Latias, although Calm Mind variants are still capable of setting up. Mew is prone to causing switches, making U-turn a solid choice, especially if entry hazards are in play. It should be noted that without investment, all of these coverage moves are quite weak. Each moveslot is really important to Mew, so make sure you consider carefully before replacing one of Mew's moves.

While this variant of Mew is incredibly durable, it still has trouble dealing with a select few Pokemon. Both Latias and Latios are capable of using Mew as setup fodder, completely disregarding most of its moves. Heatran is capable of completely walling Mew, only fearing the rare Aura Sphere. Tyranitar is a fantastic partner, as it can easily dispose of both Latios and Latias and is capable of walling Heatran with his gargantuan Special Defense stat in the sand. Trick Room Reuniclus is a troublesome foe, as not only does it wall Mew, it's also immune to status and cleanly 2HKOes Mew with Shadow Ball. Scizor happens to counter Reuniclus and can even take on Latios and Latias to a certain extent. Hydreigon can easily switch into Mew and obliterate it with its Dark STAB moves. Chansey is a phenomenal partner, as it can counter Hydreigon and almost every special attacker, most notably Latios and Latias. Chansey shares decent synergy with Mew, because between the two of them, they are capable of walling the majority of the metagame.

To show the power that Mew can bring to the table, here are some calculations, assuming Mew has one Nasty Plot boost:

• +2 LO Psyshock vs 252 HP / 252 Def Bold Blissey: 72% - 84.9%
• +2 LO Psyshock vs 252 HP / 252 Def Bold Chansey: 53.3% - 62.8%
• +2 LO Aura Sphere vs 252 HP / 252 SpD Sassy Tyranitar: 101% - 118.8%
• +0 LO Fire Blast vs 252 HP / 216 SpD Sassy Ferrothorn: 109.1% - 128.4%
• +2 LO Shadow Ball vs 248 HP / 216 Def Bold Jellicent: 89.8% - 106.2%
• +2 LO Fire Blast vs 252 HP / 0 Impish Gliscor: 101.4% - 119.5%
• +2 LO Fire Blast vs 252 HP / 0 Impish Hippowdon: 88.1% - 103.8%
• +2 LO Fire Blast vs 252 HP / 252 SpD Careful Jirachi: 103% - 121.3%

Leftovers is an alternative to Life Orb, increasing Mew's overall survivability, but at the cost of some firepower. A Lum Berry is useful as it allows you to avoid status once, which helps in taking out Pokemon that rely on status to beat Mew. The EVs are pretty standard fare, max Speed EVs are used to tie with Pokemon that have base 100 Speed and max Special Attack EVs are used to attain the highest possible Special Attack. A Modest nature with 220 HP / 252 SpA / 36 Spe may be used to increase Mew's bulk and further boost its damage potential, securing a few more OHKOs at +2, however this noticeably reduces Mew's Speed and its ability to outspeed certain threats. Specifically, Mew loses the ability to outspeed Haxorus and Hydreigon, and Speed tie with opposing base 100 Speed Pokemon such as Salamence, Volcarona, Celebi, and Jirachi.

Just like in the previous set, Mew has a ton of move options to choose from. Baton Pass is an interesting move to use on Nasty Plot Mew. It weakens Mew's ability to sweep by replacing a coverage move, but it allows Mew to make a hasty retreat should a counter switch into it. Mew can simply pass along those Nasty Plot boosts, making it a hybrid sweeper and team player. Baton Pass also helps Mew differentiate itself from other powerful Nasty Plot users such as Azelf. Softboiled gives Mew reliable recovery and is effective against Stall teams that rely on wearing down opposing sweepers. Softboiled works particularly well with Life Orb, because it allows Mew to keep its power without compromising its bulk. Unfortunately, as with Baton Pass, it cuts down on Mew's sweeping ability by eating up a coverage move.

Similarly to any other sweeper, Mew appreciates the presence of entry hazards to achieve several OHKOs. Blissey is typically OHKOed by a boosted Psyshock if Stealth Rock and a layer of Spikes are on the field. Reliable entry hazard users, such as Skarmory and Ferrothorn, are good partners to Mew for this very reason. While Nasty Plot Mew is incredibly difficult to outright counter, it has several checks that keep it from demolishing teams. The Pokemon that can check Mew are completely dependent on Mew's coverage moves. Specially defensive Jirachi is a strong counter if Mew isn't carrying Fire Blast while Reuniclus is very reliable if Mew isn’t carrying Shadow Ball. Faster Pokemon, such as Latias, Latios and Gengar, can switch into a resisted attack or Nasty Plot and force Mew out with their powerful STAB attacks. Tyranitar is a solid partner for Mew because it can counter Latias and Latios and check Reuniclus. Bulky Scizor is capable of checking Latias and Latios as well as outright countering Reuniclus. Unlike Tyranitar, it doesn't summon sandstorm, keeping Mew from taking unnecessary sandstorm damage.

Lum Berry momentarily allows Mew to dodge harmful status such as paralysis and sleep, and is very useful in conjunction with Synchronize and Taunt. Leftovers can be used to increase Mew's overall bulk and it can lessen entry hazard damage, however it should be noted that Mew cannot take any sort of status, increasing the importance of Taunt. Leftovers isn't recommended because there are times when status is unavoidable. The EVs on this set attempt to give Mew the maximum amount of bulk, while still giving it enough Speed to outspeed most of the metagame after a Rock Polish. HP EVs are maxed out, while the leftover EVs are placed in Defense, providing Mew with extra insurance against the likes of Tyranitar and Scizor. A Special Defense oriented spread may be used should you want Mew to survive powerful special threats such as Choice Specs Latios without Light Screen support.

This set absolutely requires dual screen support in order to succeed. With dual screens in play, Mew is nearly impossible to OHKO, giving it ample time to set up. You should bring Mew in after one of your Pokemon have been KOed, preferably your dual screen user. Directly switching into an opposing Pokemon is unwise because Mew should remain in tip-top condition to maximize its chances of successfully pulling off a Baton Pass. Uxie and Latios deserve a mention because they can set up dual screens and are capable of using Memento, which lets Mew safely switch into the battlefield and it makes Mew nearly indestructible. Bronzong is a decent dual screen supporter, as its excellent typing and bulk gives it excellent staying power allowing it to repeatedly set up dual screens. It can also use Explosion to safely bring Mew into the fray.

Mew has a variety of Baton Pass recipients to choose from, however the right recipient is required to win matches. It should have excellent natural bulk, decent coverage, the ability to OHKO most of the metagame, and resistances to common priority moves. Lucario fits the bill for most of these categories and is hands down one of the best Baton Pass recipients in the entire metagame. At +2/+2, it can easily OHKO or 2HKO the entire metagame, and is extremely difficult to counter. Lucario's typing makes it immune to Toxic Spikes and resistant to Stealth Rock, making hard for defensive teams to wear it down. Lucario also has excellent synergy with Mew defensively, and it even has its own priority move. Latios is the perfect recipient on the special side as it's almost impossible to counter at +2/+2, resists common forms of priority, and is even immune to Spikes and Toxic Spikes.

While this variant of Mew is almost impossible to counter due to the nature of Baton Pass, there are a few Pokemon who give it trouble. Whimsicott is capable of switching in and stopping Mew's Baton Passing attempts with priority Encore. Priority Taunt users such as Tornadus and Whimsicott can also put a complete stop to Mew's Baton Passing attempts. Trick users, such as Choice Latios and Rotom-W, can cripple Mew or its Baton Pass recipients. Because this Mew lacks any offensive moves, it is a sitting duck against faster Pokemon, so powerful sweepers such as Terrakion and Landorus can set up on Mew if it hasn't used Rock Polish. Dragon Tail users are a pain, because the move itself is unaffected by Taunt, completely ruining all Baton Pass attempts. Substitute can bypass Dragon Tail, however it comes at the cost of a boosting move or Taunt. Furthermore, there are some attacks that are simply too strong for Mew to handle, even with dual screens. Choice Band Tyranitar for example, can still 2HKO Mew even with Reflect up. Mew isn't limited to passing offensive boosts; it can also pass a variety of defensive boosts as well, namely Iron Defense and Amnesia. Entry hazard users, particularly Ferrothorn and Forretress, are acceptable teammates because they help bypass Pokemon with the abilities Sturdy and Multiscale, and grant your sweepers even more OHKOs.

The EVs are standard fare, allowing maximum power for Explosion (and Zen Headbutt if used). Another item to consider is Life Orb. It increases Zen Headbutt's damage output, although its boost to Explosion is less than that of Normal Gem's.

Care must be taken with this particular set. If your opponent has Espeon, Xatu, or a probable lead Starmie, it is best to save Mew and lead with something else. Explosion is a high risk/high reward move, especially if your opponent has a Ghost-type on their team. Though momentum might be retained through a free switch-in, Explosion's huge base power should not be forgotten. Checks to this set include Life Orb Gengar, Choice Specs Latios, Choice Band Garchomp and Terrakion, all of which outspeed Mew, and can threaten it with high-powered STAB attacks. Landorus is also threatening, with a +1 Sand Force-boosted Earthquake OHKOing Mew 43.75% of a time. Therefore, support of your own is necessary. Scizor makes quick work of opposing Gengar, and it can also check Starmie, which is notoriously hard to deal with, handily. Though it shares a Bug-type weakness, Tyranitar can be a handy partner for Mew and the rest of the team. In addition to setting up permanent sand with its ability, Tyranitar is a good counter to Espeon and Xatu, while being a reasonable check to Starmie and Latios so long as it avoids a Water-type move. All four can be trapped thanks to Pursuit or outright KOed via Crunch. Gengar also falls prey to Tyranitar, but Tyranitar must be wary of Focus Blast. Landorus, Dragonite, and just about any other sweeper appreciate Mew's ability to set up Stealth Rock; additionally, Landorus and Dragonite can switch in to opposing Landorus's Ground-type attacks should you wish to save Mew's Explosion. Rotom-W is another who appreciates a free switch in on Earth Power or Earthquake and makes quick work of Landorus with STAB Hydro Pump.