Offensive (Chinchou) @ Leftovers  
Ability: Volt Absorb  
EVs: 252 SpA / 4 SpD / 252 Spe  
Modest / Timid Nature
IVs: 0 Atk  
- Thunder Wave / Toxic
- Hydro Pump  
- Thunderbolt  
- Ice Beam

Rest Talk (Chinchou) @ Leftovers  
Ability: Volt Absorb  
EVs: 252 HP / 252 SpD / 4 Spe  
Calm Nature  
IVs: 0 Atk  
- Rest  
- Thunderbolt  
- Surf / Ice Beam
- Sleep Talk  
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Optional Move(s):
- Thunder
Optional Item(s):
- Mystic Water
Optional Ability:
- N/A
Optional EV/IV(s):
- N/A
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Overview: Chinchou stands out in ADV ZU thanks to its ability Volt Absorb and its valuable STAB. Its offensive set is tough to switch into, while its defensive set is one of the best answers to teams that utilize Rain Dance.
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Offensive: Chinchou's mediocre special attack is more than made up for thanks to its typing and high base power attacks. Thunder Wave provides support for slower teammates and itself such as Cubone, bulky Castform, and Pidgeotto. It also allows Chinchou to cripple walls that are immune to Toxic such as Koffing, Dustox, and Magnemite. Toxic can be run specifically for Lileep as all defensive Lileep sets avoid a 2hko from Ice Beam. Hydro Pump is Chinchou's main STAB that is able to chip or OHKO Pokemon that may try to switch into Thunderbolt such as Elekid, Rhyhorn, and Spoink. Thunderbolt allows Chinchou to hit opposing Water-types such as Seaking, Horsea, and Staryu. Ice Beam provides Chinchou with coverage that keeps it from being walled by Grass-types like offensive Sunflora and physically defensive Lileep. Modest nature allows for the strongest damage output, but Timid notably outspeeds all Cyndaquil unboosted Growlithe. 
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Rest Talk: Chinchou can make use of its defensive typing thanks to its above-average HP stat and use of Rest and Sleep Talk. Thunderbolt is Chinchou's primary STAB option, which allows it to check Rain Dance abusers such as Horsea, Luvdisc, and a weakened Seaking. Surf allows Chinchou to OHKO Pokemon that are immune to Thunderbolt such as Rhyhorn and Cubone. It also prevents Chinchou from being walled by Magnemite. Ice Beam can be used instead to chip Grass-types that would otherwise come in for free such as Lileep, Bayleef, and Sunflora, and provides nearly-unresisted neutral coverage, only unable to significantly damage Magnemite and opposing Chinchou. 
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Other Options: Offensive Chinchou can be used on teams that utilize Rain Dance. Thunder gives Chinchou an even more powerful Electric-type STAB which allows it to OHKO opposing Seaking and heavily chip Electric-type resists such as Elekid. Hydro Pump in conjunction with Mystic Water allows Chinchou to 2HKO common switch ins such as Dustox and physically defensive Lileep. Surf is always an option over Hydro Pump for reliable accuracy, but the power difference is noticeable, especially when considering Chinchou’s low base Special Attack stat of 56. 
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Checks and Counters: Specially defensive walls such as Sunflora and Dustox (and Lileep, to a lesser extent) can all handle Chinchou. Dustox is worth noting due to its use of Toxic which hinders Chinchou's ability as an offensive threat. Sunflora can also use Chinchou as setup fodder if it has Growth or an opportunity for a free Leech Seed. Elekid and Growlithe can 2HKO offensive Chinchou with Hidden Power [Grass] but neither appreciates taking a Hydro Pump. Physical breakers such as Aipom, Pidgeotto, and Tailow can all outspeed and OHKO Chinchou with their Normal-type STAB. A healthy Seaking is able to check offensive and defensive Chinchou thanks to Megahorn but struggles to check either set if it is weakened. Spikes users such as Snorunt and Pineco can severely limit Chinchou's switch in opportunities.
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