Vaporeon is among the few Pokemon who can claim to be a true bulky Water-type Pokemon of DPP OU. In a metagame rife with residual damage from sandstorm, entry hazards, and more, having a bulky Water-type Pokemon with the ability to pass Wish is invaluable to any team. Within a tier of heavyweights, Vaporeon shines as one of the few Water-types that take minuscule damage from Grass Knot, making it a terrific Infernape counter. Vaporeon is also the best Water-type to switch into other Water-type Pokemon due to its ability, Water Absorb.
Despite its unique attributes as a Water-type, Vaporeon has serious issues with various moves and threats. Vaporeon is deathly afraid of Toxic, as unlike Suicune, it will typically be unable to Rest away the status. Additionally, Vaporeon has issues with its inability to instantly heal itself like Milotic, which can be exploited by opponents. Vaporeon is often the opponent's first target, given Vaporeon's essential support role on teams that use it; teams tend to collapse after Vaporeon has been felled. If you choose Vaporeon for your team, it's important to do so with its specialties in mind, but in any case it will perform the chosen job admirably.
With a great base 130 HP stat, decent defenses, and access to a useful move in Wish, Vaporeon becomes an incredible support member in the OU metagame. Vaporeon can heal those who lack a recovery move and generally keeps the team at a good level of health. Pokemon like Dragonite and Gyarados, who are constant victims of Stealth Rock, appreciate Wish in any case.
Protect is the second most important move of the set, because it allows Vaporeon to reliably heal itself and keep passing Wishes. Also, Protect is a handy move for scouting purposes and restores HP thanks to Leftovers. Surf is the obligatory STAB move, and keeps Gliscor, physically defensive Skarmory, Infernape, and Heatran at bay. The last moveslot has several notable options. With Hidden Power Electric, Vaporeon becomes one of the best counters to Gyarados, even those who carry Taunt, and can deal with other opposing Water-types. On the other hand, Ice Beam keeps Dragonite, and Grass-type Pokemon in general, in check. You can also use Toxic, which when coupled with Wish and Protect makes Vaporeon able to stall numerous Pokemon that it can't harm greatly, such as specially bulky Pokemon and Pokemon who resist Surf.Team Options & Additional Comments >>>
Vaporeon is usually seen as a bulky Wish passer, but many people forget its fantastic 110 base Special Attack. With Choice Specs, Vaporeon becomes an admirable offensive Pokemon that fits very well on offensive teams that could use Wish support.
Surf, Vaporeon's primary attacking option, is a reliable STAB move that, when boosted by Choice Specs, becomes enormously powerful. Hydro Pump is an alternative to Surf that allows Vaporeon to hit considerably harder. For instance, with Stealth Rock in play, 0 HP Jirachi, 252 HP / 0 Special Defense Rotom-A, and even specially defensive Skarmory are OHKOed by Hydro Pump. Ice Beam and Hidden Power Electric provide additional type coverage, dispatching most Grass- and Water-types who resist Surf, such as Celebi and Gyarados, respectively. Wish is the recommended option for the last slot, as it gives Vaporeon the opportunity to set up Wish against a threatened opponent and heal one of its teammates that better handles the opponent's switch-in. Wish can also be used to heal Vaporeon itself, though use it at your own risk as Vaporeon may be set up on by the opponent. Signal Beam is another move to consider, mainly in order to annihilate Celebi, although Ice Beam already does a lot of damage to it.Team Options & Additional Comments >>>
Baton Pass Vaporeon is a staple of OU Baton Pass teams for its defensive aptitude, 101+ HP Substitutes, and access to numerous support options that Baton Pass teams crave. Vaporeon's ability to heal its teammates with either Wish or Aqua Ring is fundamental to the team's ability to outlast your opponent's onslaught long enough to finish the chain.
Baton Pass is necessary to pass on both what is sent to Vaporeon and what it sets up. One of the biggest lures of Vaporeon on Baton Pass chains is its base 130 HP stat, which enables the passing of immensely bulky Substitutes. In the third slot, Vaporeon has many options that it can run effectively. Acid Armor buffs your team's Substitutes and your entire chain with added Defense, which will enable Pokemon like Ninjask and Smeargle to accomplish their goals even against powerful Pokemon like Metagross and Scizor. Wish provides healing the turn after use, which enables it to be Baton Passed to teammates that need the HP. Aqua Ring, unlike Wish, provides a more gradual healing effect that can be included in the Baton Pass chain and passed around to the rest of your team. For the final move, it is recommended that Vaporeon use Surf. Surf has excellent neutral coverage in one move and prevents Vaporeon from being Taunt bait. Roar is usable over Surf for the ability to phaze opposing Skarmory and Vaporeon who typically carry phazing moves of their own, although at the cost of being very vulnerable to Taunt.Team Options & Additional Comments >>>
Vaporeon has some interesting options that it can use in its sets, but generally what you see is what you get in the above sets. Muddy Water can be used over Surf just about anywhere for its secondary effect, but the reduced accuracy is an enormous turnoff. Haze can be useful as a means of removing stat boosts from last-Pokemon Suicune, but generally Roar is the better choice for racking up entry hazard damage in the earlier game. Heal Bell is usable for supporting the team and keeping Vaporeon safe from status, Toxic in particular, but most sets simply do not have room for it and other Pokemon function better as dedicated clerics. Fake Tears can be useful for forcing additional switches, but Vaporeon almost always has more useful things to be doing with its moveslots. A set based around Curse could work in some instances, but Umbreon does it better, and that says something because Umbreon barely does it well at all in the first place.
Checks and Counters
Various Pokemon can be a menace to Vaporeon. Grass-types, such as Shaymin, Celebi, Breloom, and Roserade, can switch in with very little care if Vaporeon lacks Ice Beam. Similarly, Electric-types like Rotom-A, Jolteon, and Zapdos can get in on neutral Surf with their respectable bulk and use their STAB moves to hit Vaporeon for super effective damage, and in some cases, score the OHKO. Opposing Vaporeon make great switch-ins, since Vaporeon lacks ways to significantly damage itself without the help of Toxic. Without Hidden Power Electric, Taunt Gyarados has free reign to set up Dragon Dances, and the likes of Empoleon and Tentacruel will have no problems switching in and setting up as well. Roar helps a lot against Kingdra, who can otherwise use Dragon Dance on Vaporeon without anything to worry about; Roar is also a good option to deal with bulky Water-types such as Calm Mind Suicune and the aforementioned Empoleon. Blissey, of course, is a nightmare for Vaporeon since she can sponge all of its attacks thanks to her massive HP and Special Defense stats; however, Toxic can seriously threaten Blissey and eventually force her to switch out.