I've been given permission by PKGaming to take over the analysis for Jolteon (Baton Pass) since Hyperbeem hasn't worked on the analysis for ages, hasn't responded to either my messages or those of AccidentalGreed, and the set he's used is largely the one I suggested anyways. Furthermore, he's been doing other things on the forums in the meantime, and the descriptive text is largely based on the old analysis with Stored Power.
name: Baton Pass
move 1: Substitute
move 2: Baton Pass
move 3: Thunderbolt
move 4: Hidden Power Ice
item: Leftovers / Life Orb
ability: Volt Absorb
nature: Timid
evs: 4 Def / 252 SpA / 252 Spe
Why this set deserves to be on-site
name: Baton Pass
move 1: Substitute
move 2: Baton Pass
move 3: Thunderbolt
move 4: Hidden Power Ice
item: Leftovers / Life Orb
ability: Volt Absorb
nature: Timid
evs: 4 Def / 252 SpA / 252 Spe
Why this set deserves to be on-site
- It is commonly assumed that Jolteon runs a Specs set, and given that Specs Jolteon has both excellent power and speed, the opponent is often forced to respond with a defensive pokemon such as Blissey or Ferrothorn.
- Because of this, Jolteon finds many opportunities to scout and set up a Substitute, gauging the opponent's reaction. Jolteon can then Baton Pass this Substitute to get a setup sweeper in for free and immediately steal the opponent's momentum.
- Meanwhile, Jolteon is still a highly useful revenge killer that has a powerful STAB in Thunderbolt and excellent coverage in OU with Hidden Power Ice. Ground types like to switch into Jolteon on a predicted Specs Volt Switch, and get thoroughly wrecked by Hidden Power Ice whilst Jolteon remains behind the safety of a Substitute.
- Leftovers is the default item since it provides Jolteon with greater longevity and allows it to play the Substitute game more times in a match if necessary. However, Life Orb is also welcome if you want the extra power, although the recoil combined with Substitute's HP draining and possible sandstorm damage can be discouraging.
- This Jolteon can be used on a number of different teams and in a number of different playstyles. In bulky offense, this Jolteon can be used both as a fast revenge killer (outspeeding +1 Max Speed Adamant Dragonite and Gyarados is a boon) and as a means of getting in setup sweepers more securely. In Drizzle teams, Jolteon also gets to abuse a powerful STAB Thunder, giving it more power and the ability to cripple switch-ins with Paralysis should it be desired. In dedicated Baton Pass teams, Jolteon makes a good link in the chain due to its immunity to Thunder Wave, and can use offensive boosts to sweep through opposition with its great neutral coverage and amazing natural speed. It also has Stored Power if you want to use it in this context.
- Be wary after the first time you use Substitute. The opponent will likely have caught onto your strategy and will possibly just attack you to break any Substitutes you try to put up. Don't be overzealous when you can't afford to.
- Charge Beam can be used over Thunderbolt if you want Jolteon to actively pass boosts, but this largely isn't necessary for most ideal recipients and it detracts from Jolteon's role as a revenge killer. Work Up can also be used over Hidden Power Ice, should you be fine with sacrificing the coverage.
- A defensive EV spread with EVs in HP instead of SpA can also be used, although the extra bulk doesn't really help Jolteon as a scout and only weakens it as a revenge-killer. It can be useful for making larger Substitutes, however.
- Magnet can be used as an alternative item, boosting the power of Thunderbolt to levels similar to Life Orb, but without the recoil that synergises poorly with Substitute. It's also more effective at bluffing a Choice set if you decide to use Thunderbolt early in the game, making the opponent overconfident in the future. Expert Belt is also viable in this sense, giving HP Ice more power when it needs to be used but not boosting Thunderbolt on neutral hits.
- Good recipients for Jolteon's Substitute include bulky Swords Dance Scizor, who can come in on all Ferrothorn that try to block Jolteon and more or less guarantee a kill (Power Whip and Gyro Ball can't break the Substitute when Scizor's in) since Jolteon itself can deal with Skarmory. Gyarados is also a great option, since the Dragon Dance + Taunt set appreciates having an initial Substitute, and it can come in on Ground attacks aimed at Jolteon easily (meanwhile, Jolteon can come in on Rotom-W aiming to force Gyarados out, if you predict well) Lucario is also useful since it can come in on most Tyranitar that come in to wall you (especially on Drizzle teams) and maintain the Substitute whilst threatening to boost in either direction. Again, Skarmory is dealt with by Jolteon.
- Counters to the traditional Specs Jolteon set are all beaten if this set is partnered up with a specific recipient (preferably Scizor for Ferrothorn, Gyarados for Blissey and Lucario for Tyranitar), but if you lack one of these then the respective counter might be able to reduce Jolteon's effectiveness until you otherwise remove it. Meanwhile, Whimsicott can come in and Encore Jolteon if it uses Substitute or Thunderbolt, and since these are the two attacks you should be using initially, this is bad. If you lack Scizor, Latias is also a good response since it can set up a Substitute of its own or Calm Mind whilst Jolteon is busy. All in all, the counters for this set largely depend on what recipients you are running alongside it, apart from Whimsicott.