NFE Poisonium Z Will-O-Hex (Haunter) @ Poisonium Z  
Ability: Levitate  
EVs: 4 Def / 252 SpA / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Sludge Wave
- Will-O-Wisp
- Hex
- Substitute / Destiny Bond / Hidden Power [Fighting]

NFE Choice Scarf (Haunter) @ Choice Scarf  
Ability: Levitate  
EVs: 4 Def / 252 SpA / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Sludge Wave  
- Shadow Ball  
- Hidden Power [Fighting]  
- Dazzling Gleam / Trick
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Optional Move(s): 
- Energy Ball
- Hidden Power [Fire]
- Taunt
Optional Item(s): 
- Fairium Z
- Ghostium Z
- Life Orb
Optional Ability: 
- N/A
Optional EV/IV(s): 
- N/A
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Overview: With a fantastic offensive typing, a great base Speed stat and a variety of coverage and utility moves, Haunter distinguishes itself as one of the biggest offensive threats in the current metagame. 
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Poisonium Z Will-O-Hex: Poisonium Z Haunter hits Grass- and Fairy-types such as Clefairy, Servine, Quilladin and Togetic very hard and provides a hard hitting STAB Z-move against most neutral targets. Hex is complemented by Will-O-Wisp and lets Haunter cripple physical threats such as Fraxure and Metang and Pursuit trappers such as Alolan Grimer, Krokorok and Pawniard. Will-O-Wisp also wears down other bulky Pokemon and boosts the power of Hex to 130 Base Power. Hex gives Haunter a strong neutral STAB attack against most of the Pokemon in the metagame and also hits Ghost- and Psychic-types such as Misdreavus, Dusclops and Metang for super effective damage. Haunter's fourth moveslot is fairly customizable; Substitute allows Haunter to ease prediction and get a free Substitute on a sack or on very passive Pokemon; Destiny Bond lets Haunter 1v1 with the opposing Pokemon and Hidden Power Fighting lets it hit Pawniard and Krokorok harder.
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Choice Scarf: Choice Scarf Haunter serves as a decent revenge killer in the tier, capable of revenge-killling +1 Fraxure, Krokorok and Hakamo-o as well as outspeeding the likes of unboosted Electabuzz, Frogadier and Kadabra. Shadow Ball hits the aforementioned Ghost- and Psychic-types hard and provides a good neutral STAB attack against most of the tier. Dazzling Gleam hits Dark-, Dragon- and Fighting-types such as Machoke, Fraxure, Krokorok and Hakamo-o hard. Trick can be used to cripple and neuter bulky walls that may switch into Haunter such as Roselia, Mareanie and Sliggoo at the expense of Haunter's Choice Scarf.
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Checks & Counters: Alolan Grimer is the best Haunter counter in the metagame. It is capable of switching into Will-O-Wisp or any attack, tanking any coverage hits and trapping Haunter with Pursuit or OHKOing it with Knock Off. Munchlax is also a fantastic Haunter counter, able to shrug off hits, Pursuit trap and even get a boosted Facade if it is burned. Both Krokorok and Pawniard have to be more careful about switching into a Will-O-Wisp or a coverage move but both can Pursuit trap Haunter on a free switch-in, unless the Haunter is carrying Hidden Power Fighting. Specially defensive walls such as Roselia and Sliggoo are also capable of tanking hits from Haunter and forcing it out or weakening it slowly.
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