Stunfisk carves itself a notable niche in the PU metagame as one of the best status spreaders for balanced teams in the tier. With its reasonably good bulk, Stunfisk is able to paralyze opponents with its ability or Discharge, or poison them with Toxic. Stunfisk also has access to Stealth Rock, which provides good team support. Stunfisk makes for a good counter to common Electric-types in the tier because of its unique Ground / Electric typing, as well as a good check to physical attackers that may be reluctant to attack due to Static. However, Stunfisk's weaknesses to the ever-so common Water-, Ice-, and Grass-type attacks make it difficult to stay in for very long. Stunfisk also has a very, very low Speed stat, leaving it outsped by the entire tier bar Avalugg. Stunfisk also has no reliable recovery outside of the somewhat unreliable Rest. Lastly, like all walls, Stunfisk is very susceptible to Toxic and burns, which requires it to have cleric support.
move 1: Stealth Rock
move 2: Discharge
move 3: Earth Power
move 4: Toxic
evs: 252 HP / 252 Def / 4 SpD
Stealth Rock provides the utility of wearing down each foe that switches in. Discharge is a STAB move that has a high chance to paralyze, allowing Stunfisk to cripple opposing Pokemon and sweepers. Earth Power is a good STAB move that provides coverage on opposing Electric-types, such as opposing Stunfisk. Toxic is a good move to cripple opposing walls that are not hit hard by Stunfisk's other attacks, and it has good synergy with Earth Power, as Earth Power threatens Poison- and Steel-type Pokemon that attempt to switch into Toxic. Yawn is another option if Stunfisk wants to force switches or immobilize the opponent. Rest is also an option, as it recovers all of Stunfisk's health; however, while Stunfisk is bulky, it is very risky to keep it in while it is unable to do anything.
252 HP EVs add to Stunfisk's overall bulk, allowing it to sustain more hits and spread more status. 252 Defense EVs with a Bold nature maximize Stunfisk's Defense stat, allowing it to take any physical hit well and possibly paralyze the opponent with Static. However, a specially defensive spread can be used to take hits from special attackers. The aforementioned Static is the ability, as it has a high chance to paralyze the opponent if hit on contact. Leftovers are used for passive recovery, as Stunfisk has no other method to restore HP except the unreliable Rest.
Stunfisk should stick around throughout the match and spread status with Discharge and Toxic to cripple most of the opposing team. Stealth Rock is best used after Stunfisk has already induced status or if it forces a switch due to type advantage. With its good Defense and Static, Stunfisk does a great job of keeping physical attackers, such as Dodrio, Purugly, and Scyther, in check. This means that Stunfisk can pivot into physical attacks to try to activate Static. U-turn, in particular, is a great attack to pivot into, as users of the move are normally reliant on being quick. That being said, Stunfisk should not pivot recklessly into attacks that are powerful, as they can easily wear it down.
Stunfisk's paralysis support is greatly appreciated on balanced teams by Pokemon that are relatively slow albeit powerful, such as Bouffalant and Flareon. These two Pokemon also can cover Grass-types for Stunfisk. Garbodor, Roselia, and other hazard setters can set their hazards in combination with Stunfisk's Stealth Rock to apply extreme pressure to the opponent. Grass-types such as Roselia and Serperior can keep Water- and Ground-type Pokemon at bay, making them good partners. Clerics such as Lickilicky and Togetic are vital partners for sets using Rest, as Stunfisk usually is unable to risk three turns sleeping. In general, clerics are good partners, as they rid Stunfisk of poison and burns and can provide Wish support for sets not using Rest. Spinblockers such as Haunter can also keep Stealth Rock on the field, as well as other hazards. If Defog is a threat, Purugly is a good partner, as the Evasion drop from Defog activates Defiant and boosts Purugly's Attack by two stages. Swanna and Scyther also have great synergy with Stunfisk, while Stunfisk can block Volt Switch for them, which they both despise.
Choice Specs is a viable option on Stunfisk, as it finds a lot of opportunities to switch in and can do surprisingly good damage. Sleep Talk is an option to use Rest more effectively, but Stunfisk doesn't have enough space to fit it in. Foul Play seems like a good option to hit physical setup sweepers, but it is rather weak without a STAB boost, and Stunfisk would much rather use a status-inducing move. Scald has a chance to burn but is usually inferior to Discharge, as it has worse coverage, doesn't get a STAB boost, and doesn't always cause a burn, whereas Discharge is also backed up by Static. Protect can be used to rack up Toxic damage and Leftovers recovery, but Stunfisk will rarely have a slot for it. Sludge Wave can hit Grass- and Fairy-types, but it is rather weak. Thunderbolt is better on stall teams which would rather have Stunfisk poison opponents with Toxic, as well as having a higher damage output.
Checks & Counters
**Grass-types**: Grass-types aren't threatened by any of Stunfisk's attacks and can OHKO it or set up on it. Roselia in particular is a threat, as it has the bulk to take Earth Power, has Natural Cure to deal with status, and resists Stunfisk's coverage moves, while it sets up Spikes or OHKOes.
**Ground-types**: Faster Ground-types, such as Marowak, usually will outspeed Stunfisk and hit it hard with a STAB move, although Stunfisk carrying Scald can take a hit and potentially burn. Pokemon that carry Earthquake as a coverage move also threaten Stunfisk.
**Water-types**: Water-types, such as Simipour and Frogadier, can hit Stunfisk hard with their STAB moves but must be wary of Stunfisk using Discharge, which will either OHKO or possibly paralyze in return.
**Status**: Poison and burn instantly puts a timer on Stunfisk's longevity and negates its Leftovers recovery, wearing it down quickly. Toxic in particular stacks up, making it even harder for Stunfisk to stay on the field. Stunfisk that carry Rest are less threatened by status, especially with cleric support.
**Taunt**: Taunt stops Stunfisk from using its utility moves, which really cripples it role as a status spreader. Stunfisk is also rather weak, which means any offensive move it is forced to use will not be doing too much damage.
**Clerics**: Clerics, such as Lickilicky and Togetic, can eliminate the status Stunfisk spreads, and they can easily wall it and wear it down. Most clerics also have reliable recovery, so they cannot be worn down by repeated attacks from Stunfisk.
**Entry hazards**: Entry hazards, namely stacked Spikes, will wear down Stunfisk each time it switches in. Two layers of Toxic Spikes will badly poison Stunfisk, which makes it very hard for it to properly function as a wall.
**Offensive Pressure**: Despite heavy defensive investment, Stunfisk struggles against offensive pressure, especially special attackers, as most invested attackers can still hit it hard and make it easier to wear down. Stunfisk only has Leftovers and Rest as recovery options, so it cannot stick around indefinitely.