For most of its existence, Weavile has generally been regarded as a niche Pokemon. This has not changed in Black and White. Fortunately for Weavile, its niche skills are readily in demand with the influx of both old and new Dragons alike, giving it more targets for its STAB Ice attacks. Furthermore, STAB Dark and access to Pursuit allows it to trap and KO some important targets in the OU metagame. The party stops once you recognize its poor defenses, and weakness to Stealth Rock, but with the proper support, his unrivaled prowess as a dragon slayer, psychic spook, and potent revenge killer all in one will demonstrate exactly why it remained OU for the entirety of the previous generation.
A standard Life Orb set manages to accentuate all of Weavile's best attributes: 120 base Attack, 125 base Speed, STAB Pursuit, and being one of the few viable users of STAB Ice attacks. The main attractions here are its exceedingly useful Ice Shard and Pursuit. With these moves in tow, an Outraging Dragon is never truly safe, fearing a swift icicle to the face in the middle of its rampage. While switching in is almost never advisable, Weavile can usually catch these targets after they take something else out, leaving them trapped, helpless, and vulnerable to the inevitable KO. Choice Band augments Weavile's firepower even more, allowing to net some KOs that Life Orb falls short.
Pursuit is arguably one of the most useful moves in the game, punishing predicted switches and effectively trapping enemies. Less defensively inclined targets, such as Gengar, Starmie, and Latios, are often KOed regardless of whether or not they switch (with a little prior damage required in the case of Latios), adding to Weavile's repertoire the technical role of a 'trapper'. Be wary of using this on bulkier Psychics such as Reuniclus, however, which do not fear Weavile's Pursuit and can either cripple it with status, or in Reuniclus's case, OHKO it.
Thankfully, Weavile's role as a revenge killer is not limited to two 40 Base Power attacks. Weavile also has access to Low Kick, which offers excellent coverage alongside Weavile's Dark-type moves, as well as having the ability to OHKO both bulky and heavy targets such as Terrakion, Tyranitar, and Heatran. It can also catch Weavile's long-time nemesis, Scizor, on the switch for decent damage.
The choice between Ice Punch or Night Slash on the final slot should be made while considering how your team handles specific Dark- or Ice-type weak enemy Pokemon. If you fear bulky Psychics and Ghosts enough to use it, Night Slash is a viable option, but Ice Punch is generally more useful for taking on the many bulky Grass-, Flying-, Dragon-, and Ground-types that currently reside in OU. Additionally, Ice Punch is often its strongest option against targets it can only hit for neutral damage.Team Options & Additional Comments >>>
The term of the day is late-game cleaner, and no better term exists to describe this set. Due to Weavile's lack of defenses and by extension, relatively low number of chances to set up, it's best to keep its function as a revenge killer in mind earlier in the game and attempt a sweep only when its counters have been cleared or at least weakened. As previously mentioned, setup opportunities are very few in number, but still exist. For example, a Scizor or Tyranitar Choice-locked into Pursuit leaves Weavile an open opportunity to set up as they switch out. Be wary of setting up on Scizor, as it can come in later and OHKO with Bullet Punch if it hasn't been adequately weakened prior to setup.Team Options & Additional Comments >>>
Sadly, Weavile's usable movepool is fairly limited. Brick Break is probably the first option that comes to mind, as it fits on all of its movesets and can be used as a more consistent option than Low Kick—consistently weaker, that is. Fake Out and Counter make an anti-lead set possible, but not advisable, considering the presence of team viewing mechanics and a stronger, bulkier metagame that does not encourage the use of suicide leads. Taunt is a viable option on Life Orb sets to prevent the likes of Ferrothorn and Skarmory from setting up on Weavile.
Checks and Counters
Bulky Steel-types that aren't weak to Low Kick are Weavile's greatest obstacles. Scizor can switch in on anything Weavile has safely and threaten to OHKO it with either Bullet Punch or U-turn. Jirachi is about the same in this regard, with Iron Head over Bullet Punch. Skarmory and Forretress can more or less use Weavile as an easy opportunity to set up entry hazards; Ferrothorn can also do this to a lesser extent, provided Weavile is locked into a resisted move or hasn't had the chance to boost. It can also threaten to OHKO with Gyro Ball, if necessary. In addition, bulky Water-types, barring Jellicent, wall most of its attacks and can threaten to burn with Scald.
Fighting-types are generally good for keeping Weavile in check as well. Conkeldurr is easily Weavile's biggest threat among them, as it can Bulk Up on a Pursuit-locked Weavile and continue threatening the rest of its team, or KO instantly with Mach Punch. Lucario and Infernape resist both of its STABs and can either set up or KO with priority. Ninetales is a relatively safe switch-in too, as are other less common Fire-types, such as Arcanine.