Necturna is CAP's most versatile Pokemon thanks to her access to one Sketch move, allowing her to perform a variety of roles, from spreading status to setting up entry hazards to being an offensive sweeper. With the addition of Sticky Web, King's Shield, and Spiky Shield in XY and Precipice Blades and Dragon Ascent in ORAS, Necturna got a wide array of powerful moves, giving the opponent even less of a chance of guessing which set she is running. She also has the joint-second highest base stat total of all CAP Pokemon with an impressive base 120 Attack and Special Defense, which are complimented by a decent base 100 Defense. In addition, Necturna's base 81 Speed allows her to outspeed common base 80 Speed Pokemon such as Mamoswine and Cyclohm. Unfortunately, she is still rather slow in comparison to most of the tier, which means she can be outsped and KOed by many common threats such as Colossoil and Cawmodore. Moreover, Necturna has a very mediocre base 85 Special Attack, preventing her from being able to take full advantage of her specially offensive Sketch moves. Most of all, Necturna is weak to four priority attacks as well as Knock Off, limiting her use as a sweeper and allowing slower Pokemon to deal large amounts of damage to her. Lastly, Necturna has a meager base 64 HP, meaning that her good defense stats are somewhat wasted.
Sticky Web slows down grounded foes as they switch in and allows your Pokemon to win what would otherwise be Speed ties. Will-O-Wisp can cripple physical sweepers, most notably Cawmodore, that try to use Necturna as setup bait and can be used on any physical threats in general. Shadow Sneak is a STAB priority move that allows Necturna to potentially KO Pokemon and avoid a slower Sucker Punch. Power Whip is Necturna's strongest STAB move, while Horn Leech can be used to give Necturna a form of recovery, but its lower Base Power makes it much harder to KO Colossoil. Super Fang halves the HP of any Pokemon that isn't a Ghost-type and can annoy Pokémon such as Chansey which would otherwise wall Necturna.
Necturna is arguably the best Sticky Web setter in the CAP metagame because she can block Rapid Spin courtesy of her Ghost typing. Colbur Berry in combination with full investment in HP and Defense allows Necturna to set up Sticky Web even against Colossoil, as a Knock Off from Colossoil does less than 50% with Colbur Berry. Colbur Berry also gives Necturna an opportunity to hurt Colossoil back with Power Whip, which does around 85% even with minimal Attack investment.
A specially defensive spread of 252 HP / 252 SpD / 4 Spe, a Calm nature, and Leftovers could be used, as Will-O-Wisp already deals with physical threats, but without Defense investment, Necturna cannot take any attacks from Colossoil. Focus Sash is an option to guarantee that Necturna can set up Sticky Web, but it is liable to getting broken by the Stealth Rock and other entry hazards. On the other hand, Focus Sash also allows Necturna to stop sweepers. Leftovers could be used to give Necturna passive recovery, but at the cost of Colbur Berry, which is essential against Colossoil.
Players will often predict Sticky Web Necturna to lead, so they will likely send in a Pokemon to lure the Sticky Web and then switch to Colossoil to Rebound it back, leaving you with Sticky Web on your side as well as a potentially bad matchup. Predicting this correctly and hitting Colossoil with Power Whip on the switch-in allows Necturna to set up Sticky Web and then potentially tank the second Knock Off and KO Colossoil. Similarly, Magic Bounce users, most notably Mega Sableye, can bounce back Sticky Web and Will-O-Wisp. Note that other Magic Bounce users do not appreciate being hit by Power Whip and Shadow Sneak, so they take a risk if they switch in.
Predicting a Sucker Punch allows Necturna to set up Sticky Web for free or cripple the foe with Will-O-Wisp, assuming it does not have Guts. On that note, be careful when using Will-O-Wisp on Colossoil, as Colossoil will gain a boost to its Attack if it has Guts. On the other hand, many Pokemon that wall Necturna, such as Skarmory, Scizor, and Cyclohm, don't appreciate a burn grinding down their health and, in some cases, crippling their attacking moves, so burning them on the switch can be your best bet.
Necturna is best on a team that appreciates Sticky Web, so Pokemon that lack a little bit of Speed, such as Choice Specs Sylveon, will benefit from the Speed drop that Sticky Web brings. Bisharp can be a good partner, as it covers four of Necturna's weaknesses while Necturna covers two of Bisharp's, although they are both weak to Fire and Bisharp is rather frail. Bisharp discourages Defoggers from removing Sticky Web because it gets a +2 Attack boost if it switches into Defog; in return, Bisharp benefits from Sticky Web due to its low Speed. Because opposing Bisharp can get a free Attack boost through Sticky Web, it is advisable to run a Bisharp counter, such as Haze Tomohawk or Unaware Arghonaut, which can take any of Bisharp's boosted attacks and/or counter it; Tomohawk also completely walls Colossoil, Necturna's biggest threat.
Fire types such as Heatran and Mollux resist Power Whip and can absorb Will-O-Wisp, allowing them to completely wall Necturna and OHKO her with their super effective Fire-type STAB moves, although they can't stop her from setting up Sticky Web. Therefore, a check to Fire-types is quite useful; Colossoil threatens Fire-types with its STAB Earthquake and can also force out Chansey, which can easily take a Power Whip and heal her team of burns that Necturna may have inflicted.
Pokemon with high Special Defense, such as Sylveon, can help to counter strong special attackers which can KO Necturna and are not affected by burn's Attack drop. Necturna has a nasty weakness to Knock Off, but that can be alleviated by having a teammate that can take Knock Off, such as a Fairy- or Fighting-type. Necturna is weak to several priority attacks, particularly Talonflame's Brave Bird and Mega Pinsir's Quick Attack, so a Flying-type check such as Cyclohm or Rotom-W can be a great partner.
The first moveslot contains your choice of a Grass-type STAB move: Power Whip is extremely powerful but has imperfect accuracy, while Horn Leech gives recovery but is much less powerful. Leaf Blade is a compromise, with more power than Horn Leech and perfect accuracy, unlike Power Whip. Shadow Sneak is a STAB priority move that is good for revenge killing and avoiding priority attacks from opposing Pokemon, while Shadow Claw is Necturna's only other physical Ghost-type STAB move.
The Sketch moveslot is a choice between V-create, Sacred Fire, and Dragon Ascent. Choice Band V-create allows Necturna to OHKO Mega Metagross, Skarmory after Stealth Rock, and Kyurem-B after Stealth Rock, and to 2HKO Chansey and physically defensive Mega Venusaur. However, this comes at the cost of drops in both Necturna's defenses and Speed and lower accuracy than Sacred Fire. Dragon Ascent can used to lure in and OHKO Tomohawk. Lastly, Sacred Fire works better on Life Orb sets and grants burn utility in return for losing some power.
Precipice Blades or Earthquake can be used as alternatives to lure in and 2HKO Cyclohm and Heatran, both of which can deal with Necturna quite well otherwise. Bolt Strike can be used instead of Dragon Ascent, as Choice Band Bolt Strike has a 62.5% chance to OHKO Tomohawk after Stealth Rock and will 2HKO even if Tomohawk uses Reflect or Roost, although it has an unreliable 85% accuracy. It has the added advantages of OHKOing Skarmory without dropping Necturna's defensive stats and Speed.
This set takes advantage of Necturna's good Attack stat and decent 64 / 100 / 120 bulk to be able to take hits and hit very hard. 116 EVs in Speed allow Necturna to outspeed uninvested base 95 Speed Pokemon, most notably Colossoil, as well as maximum Speed Azumarill. Choice Band allows Necturna to hit extremely hard at the cost of being trapped into a single move, while Life Orb allows Necturna to change moves but provides residual damage and less power.
If Necturna lacks Horn Leech, she has no recovery, so only switch her in when you are sure she won't take too much damage or after a teammate has fainted, allowing Necturna to revenge kill the foe. Choice Band V-create hits anything that doesn't resist incredibly hard and often guarantees KOs, but it lowers Necturna's defenses and Speed. If it is run, use V-create in the early-game to punch holes in the opposing team, then switch Necturna out. Dragon Ascent is in a similar position, except that it doesn't lower Necturna's Speed.
Physical walls such as Cyclohm, Skarmory, and Tomohawk can switch in and wall Necturna, as they all resist Necturna's Grass-type STAB moves and can take Shadow Claw fairly well, although they don't like getting hit by Necturna's Sketch moves. Cyclohm dislikes Precipice Blades, Skarmory cannot withstand Bolt Strike, V-Create, and Sacred Fire, and Tomohawk hates Dragon Ascent and Bolt Strike.
Necturna appreciates support from Gothitelle, which can trap and remove physical walls such as Cyclohm, Skarmory, and Tomohawk. Similarly, Magnezone can trap and remove Ferrothorn and Skarmory. Necturna also appreciates powerful special attackers such as Syclant and Stratagem, which can take down the physical walls that give Necturna trouble. Bisharp can outspeed and easily revenge kill Necturna with its STAB Knock Off or Pursuit, although it can't switch in on anything it doesn't resist. This means Pokemon that can take Knock Off and other powerful Dark-type STAB moves, such as Fighting- and Fairy-types and most Mega Evolutions, are good partners. Entry hazards are also very useful for Necturna, as they break opposing Focus Sashes and Sturdy and allow Necturna to get more OHKOs, most notably on Kyurem-B and Tomohawk. Lastly, Flying-type spam is everywhere, so a counter to it, such as Rotom-W or Cyclohm, will do wonders for Necturna.
Shell Smash and Shift Gear double Necturna's Speed and provide a boost to her strong Attack stat. Shell Smash gives Necturna a bigger boost but will leave her with either lowered defenses or a lack of an item. Shadow Sneak is a solid STAB priority attack while Shadow Claw is a stronger Ghost-type STAB move, though Stone Edge can be used in place of Shadow Claw to hit Ice-, Flying-, and Fire-types hard. Horn Leech grants Necturna recovery, while Power Whip is very strong but slightly inaccurate, and Leaf Blade has perfect accuracy and more power than Horn Leech. Another decent option is Thunder Fang, which hits Flying-types decently hard and is more accurate than Stone Edge.
At +2, 168 Speed EVs and a Jolly nature allow Necturna to outspeed Timid Mega Aerodactyl and Choice Scarf users with up to base 110 Speed. 108 Speed EVs with a Jolly nature can be used to outspeed Choice Scarf Plasmanta if outspeeding Choice Scarf Kitsunoh, Latios, and Latias is not important. An Adamant nature with 252 Speed EVs provides Necturna with more power and allows her to outspeed Choice Scarf Keldeo and Terrakion at +2, but she will be unable to catch the base 110 Speed Pokemon. An Adamant nature with 192 Speed EVs let Necturna outspeed Choice Scarf Plasmanta. Maximum investment in Attack allows Necturna to hit as hard as possible, while the remaining EVs are dumped into HP to give her some bulk. If running Shell Smash, Shadow Ball can be used to hit physical walls such as Skarmory and Tomohawk slightly harder; moving the 88 HP EVs into Special Attack allows Necturna to 2HKO both of them after Stealth Rock.
White Herb can be used to offset the stat drops of Shell Smash, while Focus Sash allows Necturna to survive a single powerful attack. Alternatively, Life Orb lets Necturna hit very hard and get some important KOs, most notably OHKOs against Mega Pinsir after Stealth Rock and 252 HP Kitsunoh, but at the cost of residual damage, which whittles down Necturna's already mediocre HP. Colbur Berry useful for Shift Gear sets because it lets Necturna reliably beat Colossoil and isn't broken by entry hazards.
Be sure Shadow Sneak can KO the foe, because if it doesn't, Necturna is vulnerable to several common priority attacks, especially Ice Shard, Talonflame's Brave Bird, and Mega Pinsir's Quick Attack. Necturna is also hurt badly by Sucker Punch if she doesn't use Shadow Sneak. Focus Sash and Colbur Berry sets can be used to bait and KO Colossoil while possibly regaining Necturna's health back through Horn Leech. If not running either item, be sure to remove the opponent's Colossoil as soon as possible, as it is resistant to Shadow Sneak and will OHKO Necturna with Sucker Punch.
After setting up, Necturna can outspeed essentially the entire metagame and deal serious damage in the process. Necturna is best used for late-game sweeps, when her counters are gone and she can operate much more freely. Much like with any setup sweeper, make sure you set up at a time when Necturna is not in danger of getting seriously damaged.
Gothitelle and Magnezone can trap and KO the physical walls that stop Necturna's sweep, particularly Tomohawk and Skarmory. Strong special attackers such as Mega Gardevoir, Aurumoth, and Latios pair well with Necturna, as they can take on physical walls. Tomohawk can wall Colossoil and Bisharp, while offensive variants can heavily damage Cyclohm and Skarmory with Earth Power and Aura Sphere, respectively. Tomohawk can also set up Stealth Rock, which allows Necturna to OHKO Talonflame, Mega Pinsir, and offensive Kitsunoh with a +2 Shadow Sneak. Physically defensive Rotom-W and Cyclohm can take care of Ice Shard and Sucker Punch users and Flying-types, which can annoy Necturna with their super effective STAB priority moves.
Spore allows Necturna to put her foes to sleep with perfect accuracy. Will-O-Wisp allows Necturna to burn foes, most notably due to the switches that Spore will force, crippling their Attack and whittling down their HP. This, along with maximum HP and Special Defense EVs, allows Necturna to wall all non-super effective STAB moves quite effectively. Horn Leech is a reliable STAB move that also gives Necturna some form of recovery, while Super Fang allows Necturna to halve the foe's HP and gives Necturna some wallbreaking ability. Alternatively, Shadow Claw can be used for a Ghost-type STAB move.
The set is aimed at crippling one foe with sleep while still retaining the ability to burn others if the foe switches out. Leftovers gives Necturna the passive recovery that she needs, increasing her longevity so she can spread more status. The EV spread and a Careful nature maximize Necturna's special bulk, as the Attack drops from burns mean Necturna does not fear physical attacks. An alternative EV spread of 252 HP / 88 Def / 168 Spe can be used to outspeed Bisharp and cripple it with Will-O-Wisp while thwarting its Sucker Punch.
Necturna isn't fast and struggles to take physical attacks before burning a foe, so try to bring her in on free switches or against slow special attackers. However, Spore allows Necturna to put a foe to sleep, essentially removing it from the battle until it wakes up. As a result, the opponent will often switch the sleeping Pokemon out in order to not give away free turns, allowing Necturna to either cripple the new foe with a burn or halve its health with Super Fang.
Beware of Colossoil, which is not OHKOed by a weak, uninvested Horn Leech and can bounce back Spore and Will-O-Wisp with Rebound or absorb Will-O-Wisp with Guts. Fortunately, Necturna's Grass typing means she will not be put to sleep by Spore if it is bounced back. Fire-types are immune to Will-O-Wisp, while Grass-types and Overcoat users are immune to Spore, so the opponent can get a free switch-in if they predict correctly. Also, note that Pyroak completely walls this set. Magic Bounce users, most notably Mega Sableye, can bounce both Spore and Will-O-Wisp, while Super Fang doesn't hit Mega Sableye, although Mega Diancie doesn't like getting hit with Horn Leech and can't hit Necturna super effectively with anything other than Hidden Power Fire. Therefore, be careful when spreading status against a team with a Magic Bounce user. Chansey can come in and take a Spore or a Will-O-Wisp thanks to Natural Cure and pass a Wish to a teammate. Chansey can also cripple Necturna with Toxic, although she doesn't particularly like getting hit with Super Fang. Therefore, it is advisable to switch out against Chansey with this set, preferably into a Pokémon which is immune to Toxic.
Spore and Will-O-Wisp can force a lot of switches, so an entry hazard setter such as Tomohawk or Ferrothorn is useful for wearing down the opposing Pokemon and luring in Colossoil and the Magic Bounce users that stop Necturna from spreading status. Tomohawk is also a sure counter to Colossoil and can set up Reflect, which boosts Necturna's ability to take physical attacks; Tomohawk can also use Haze on Mega Sableye that try to set up Calm Mind after switching into Necturna.
Gothitelle and Colossoil can KO or trap Chansey and other clerics, which can come in and use Heal Bell or Aromatherapy to get rid of the status that Necturna spreads or Wish pass to get rid of Super Fang damage. Necturna is easily KOed by super effective moves, most notably from Fire-types such as Talonflame or Mega Charizard X which can switch in on a predicted Will-O-Wisp, so physcial tanks such as Cyclohm and Rotom-W are great teammates.
A special attacking set with Geomancy and Power Herb can be used to boost Necturna's mediocre Special Attack to high levels and give her insane Special Defense while still allowing her to outspeed most of the metagame. However, it is outclassed by Necturna's physical sets due to Necturna's superior Attack stat. Belly Drum is also an option, boosting Necturna's already impressive base 120 Attack to insane levels. However, Necturna is too slow pull it off effectively.
King's Shield and Spiky Shield can force switches, stop sweeps, and get KOs if used correctly, although they are generally outclassed by other moves. Parting Shot gives Necturna the ability to carry momentum while also crippling opposing attackers, with the exception of Defiant Bisharp. Dark Void can be used instead of Spore to give Necturna the ability to send Grass-types to sleep at the cost of lower accuracy and susceptibility to sleep should the move be reflected by Magic Bounce or Rebound.
Necturna also has options which do not use up her Sketch move; Gravity gives Necturna's teammates some support, allowing Ground-type moves to hit Flying-types, most notably Skarmory and Cawmodore. Pain Split can be used as a viable form of recovery, while Toxic Spikes can spread poison throughout the opposing team.
Checks and Counters
Physical Walls: Physical walls such as Cyclohm, Skarmory, and Tomohawk can take Necturna's STAB moves with relative ease and can potentially stop Necturna's sweep or force her to switch out, allowing them to take control of the flow of the battle.
Taunt Users: Taunt stops Necturna from spreading status ailments, setting up her offenses, and laying down Sticky Web. Unless using the All-Out Attacker set, keep Necturna away from fast Taunt users at all costs.
Super Effective Priority Moves: Talonflame's Brave Bird, Mega Pinsir's Quick Attack, Ice Shard, Sucker Punch, and Shadow Sneak are common priority moves that can severely damage or even OHKO Necturna, with the exception of Sucker Punch should Necturna be running Colbur Berry.