Despite a crippling 4x weakness to Stealth Rock, Scyther is an extremely dangerous and often underestimated UU sweeper. Its great dual STABs provide excellent neutral coverage, and also hit many common defensive Pokemon for super effective damage (including Hitmontop, Uxie, Venusaur, and Slowbro). In addition, its high Speed and welcome resistances to Fighting and Grass means that it can check and revenge kill many common offensive Pokemon. However, Stealth Rock is hostile to Scyther, shaving off a substantial 50% of its HP; dedicated Rapid Spin support is nearly essential to ensuring success with Scyther. Despite this admittedly large flaw, mustering up the necessary support is definitely worth it when you consider Scyther's destructive potential.
Scyther has naturally high Attack and Speed, and Swords Dance and Life Orb complement its stats to make it an extremely vicious physical sweeper in UU. Scyther packs resistances to Fighting- and Grass-type moves along with an immunity to Ground-type moves, which gives it setup opportunities on quite a few popular Pokemon. However, due to its relative frailty, Scyther shines most when brought out in the late-game after its counters have been weakened and the other team has been scouted.
Aerial Ace is chosen as Scyther's STAB move of choice over Bug Bite due to its superior neutral coverage; Electric-type Pokemon aren't very common apart from Rotom (who also resists Bug Bite); most Rock-type Pokemon take more damage from Brick Break than they would from a neutral Bug Bite; finally, Steel-type Pokemon resist both Flying and Bug. Brick Break ensures Scyther isn't walled by Steelix, Registeel, and Rhyperior, and in conjunction with Aerial Ace provides perfect neutral coverage in UU with the exception of Rotom. In the last slot, Quick Attack ensures quick but frail sweepers such as Alakazam or Dugtrio won't end your sweep, and is a great way to pick off weakened set-up sweepers.
Bug Bite can be used over either of the last two attacks depending on what the rest of your team looks like—Brick Break isn't as useful if Scyther has Rhyperior or Torterra at its side, ready to take advantage of Rock- and Steel-type Pokemon; on the other hand, Quick Attack may be dropped if you feel that you're safe against speedy but frail sweepers.Team Options & Additional Comments >>>
Scyther frequently won't have time to Swords Dance and doesn't particularly appreciate Life Orb's recoil in tandem with Stealth Rock damage, so using a Choice Band is a logical alternative. The goal of this set is to chip away at the other team with repeated fast U-turns while simultaneously threatening to sweep with its powerful Aerial Ace. This means that while Rapid Spin support is appreciated by Scyther's other sets, it is absolutely vital to the success of this set.
Aerial Ace and Bug Bite are still Scyther's strongest STAB attacks, but U-turn is preferred over Bug Bite despite its inferior Base Power due to its wonderful ability to scout. Quick Attack is useful for picking off weakened sweepers who have a Speed boost under their belts. Pursuit can trap the Psychic- and Ghost-type Pokemon who frequently flee from Scyther's STAB attacks. Finally, Brick Break remains a perfect auxiliary attack for combating Steel- and Rock-types like Registeel, Steelix, and Rhyperior.Team Options & Additional Comments >>>
This set's main goal is to rely on Scyther's good bulk to pass Swords Dance boosts to a dangerous sweeper, and its effectiveness is thanks mostly to the great success of the Swords Dance set; many opponents will switch their walls into Scyther, not expecting it to be bulky enough to set up on them or pass its boost to something else. Swords Dance and Baton Pass are the most important moves as they allow Scyther to set up and pass the boosts to a sweeper. Aerial Ace is the third move to avoid being shut down by fast Taunt users such as Mismagius and Ambipom, and is a powerful STAB move with good coverage. When taking into account the Attack boosts Scyther will grab, it will dent everything that doesn't resist it, being able to grab a few KOs should the opportunity arise. The last slot offers a choice between two moves, but Substitute is often the preferred option as it protects Scyther from status moves, as well as Trick, and allows the recipient of the boosts to switch in unscratched. Leftovers is the superior item for the extra setup turn it may grant Scyther with.Team Options & Additional Comments >>>
Using a 29 HP IV on sweeper sets can give Scyther greater longevity in the long-term. This yields an HP stat of 279 instead of 281, which means Scyther loses 1 less HP from both Life Orb recoil and Stealth Rock damage. After two of these events (either a switch into Stealth Rock and a Life Orb recoil or two Life Orb recoils), Scyther breaks even; at three or more, Scyther with a 29 HP IV will actually have more HP than those with 31 HP IVs.
176 Speed EVs are a good guideline for Scyther, regardless of nature. With Adamant, it hits 290, which means Scyther can outrun Sharpedo, Jynx, and Primeape without Speed-boosting natures, while with Jolly it attains 319, which outruns all Pokémon with 95 base Speed or less. In Jolly's case, an extra 4 EVs allow Scyther to outrun Speed-neutral base 110 Speed Pokémon. Besides some specifics noted in the sets, aim for maximizing Attack and Speed. Ensure that Scyther's HP is odd, so it can switch into Stealth Rock twice. For most sets, the remaining 4 EVs are placed into Special Defense to ensure the rare Download Porygon2 won't receive a Special Attack boost.
Roost is in general a decent move, but Scyther doesn't quite have adequate defenses to use it effectively. Double Hit gets a Technician boost, so it's useful for breaking Substitutes. Thief also gets a Technician boost, but its power is still a paltry 60, and it may snag an item that is useless to Scyther.
Checks and Counters
As previously mentioned, Stealth Rock will destroy Scyther quickly, but there are also several Pokémon who can weather its assaults.
Steelix and Registeel resist both of Scyther's STABs and can set up Stealth Rock to boot. Although they are both weak to Fighting, their high Defense stats mean they can easily survive even a Swords Dance boosted Brick Break easily; Steelix can KO Scyther with Gyro Ball or Explosion, and Registeel can cripple it with Thunder Wave and wear it down with Iron Head. Steelix has the added benefit of being able to Roar out the Baton Pass set. Although Rhyperior and Regirock don't resist Bug, their physical bulkiness and STAB Rock attacks let them handle Scyther with relative ease. Rotom also resists both of Scyther's STAB attacks and can KO with Thunderbolt.
The few Pokémon who are naturally faster than Scyther can check it in a pinch, although they will all have to predict and avoid switching into a move that will OHKO them. Swellow sports a super effective Brave Bird, while Jumpluff can come into a support move like Substitute or Swords Dance and use Encore to stall Scyther while it switches to an offensive Pokémon.
Priority moves such as Mach Punch, Fake Out, and Sucker Punch will beat the sets that focus on Reversal, while they can help wear down Life Orb versions for offensive teams.