Sneasel can be found on Routes 216 and 217, Acuity Lakefront, Lake Acuity, and in the Snowpoint Temple (which, however, is post-game). Its encounter rates vary from place to place, and it is generally more common during the day than at night. The highest encounter rate in Platinum is 35%, on Route 216, whereas in Diamond and Pearl it is 25% in all locations during the daytime.
Razor Claws are available on Route 224, in Victory Road or, only in Platinum, in the Team Galactic HQ.
Many games do not allow access to Ice-types at all, or if they do, it is not too far from the endgame. Sinnoh is no exception to that rule, but it does make Ice Pokémon a lot easier to obtain, with a good few areas entirely dedicated to them. Sneasel is fairly easy to find, though not as much to catch; it will need to be weakened in moderation, so as to not faint it accidentally. After getting one, however, it will prove itself a great ally within its niche.
Sadly, the whole line gets nothing more than Ice Shard in Diamond and Pearl as far as physical Ice STAB goes, although Platinum is definitely better: Ice Punch is also available, even before reaching the point in the game where Sneasel can be caught. Needless to say, it is a line with many weaknesses, one of which is a crippling double weakness to a fairly common and powerful type, and that makes Weavile frailer than its stats would suggest. However, for experienced players, and players who know what they are doing at exactly every single given point in the game, Weavile is a good asset, not to mention one of those Pokémon that can take down some really crippling threats to any team with much more ease than any other available Pokémon could, even its own Ice colleagues.
Gym #7 - Candice (Snowpoint City, Ice-type): The lead Snover can only 4HKO Sneasel with Razor Leaf, its strongest move, so Sneasel can exploit it to put up three Swords Dances and then OHKO Snover, Sneasel and Abomasnow with Brick Break, as well as Medicham with Faint Attack. Taking on Abomasnow and Medicham is only possible this way, as they would otherwise destroy Sneasel with Wood Hammer and Force Palm respectively.
Cyrus (Galactic HQ): Murkrow and Golbat can be 2HKOed by Ice Beam, though depending on Sneasel's stats, Golbat may be only 3HKOed instead; Murkrow 2-3HKOs with Drill Peck and Golbat 4HKOs with Poison Fang, unless it goes for Supersonic instead, so mind the damage if it starts accumulating. Cyrus' Sneasel is simply defeated by Brick Break, but it does have Quick Attack; watch out if Sneasel's health is low.
Saturn (Galactic HQ): Sneasel can theoretically set up Swords Dances against Kadabra, but it is not worth it. It takes a full +6 boost to OHKO Bronzor, and Toxicroak will kill Sneasel with Brick Break regardless. Just Faint Attack the Kadabra and then withdraw.
Mars and Jupiter (Spear Pillar, tag battle with rival): Both Mars and Jupiter lead with a Bronzor carrying Gyro Ball, which comes close to 2HKOing Sneasel; if both of them use the move, Sneasel may be killed in one hit. Once they are gone, the weasel may attempt to tackle the two Golbat, but Sneasel is at a serious risk here for switch-ins, as two hits chip away the best part of its HP and the enemy Pokémon can gang up on it. Ice Beam and, if Sneasel has it, Ice Shard are also merely 2-3HKOs against them. Moreover, while Purugly can be 2HKOed clean with Brick Break, Skuntank has Flamethrower and can take Sneasel's hits quite well, but not the other way around. Unless Sneasel is the last one standing, it should not enter the battlefield at all.
Cyrus (Spear Pillar): Sneasel can 2HKO Honchkrow with Ice Beam, yet gets beaten by everything else on Cyrus' team: Crobat outspeeds and 3HKOs with Cross Poison, Gyarados nearly annihilates it with a single Giga Impact, and Weavile outspeeds and OHKOs with Brick Break.
Dialga/Palkia (Spear Pillar): No. Both Dialga and Palkia have a power that is far superior to Sneasel; Dialga can even OHKO with Roar of Time, though Palkia's Spacial Rend is not that far, either. Do not fight them.
Gym #8 - Volkner (Sunyshore City, Electric-type): Sneasel needs to avoid Raichu due to its Brick Break, but can set up against Ambipom afterwards. At +6, Sneasel's Faint Attack OHKOs Ambipom, Luxray and Octillery. If Ambipom uses Nasty Plot and Baton Pass instead, Sneasel needs to switch to the offensive right away; while Ambipom's Shock Wave deals little damage by itself, Luxray's Charge Beam and Octillery's Octazooka are both 2HKOs after a Nasty Plot boost. Fortunately, Faint Attack can 2HKO starting at one Swords Dance, so Sneasel can win either way.
Rival (Pokémon League): Weavile should not attempt to fight Staraptor, as it has no chance of OHKOing before Staraptor kills it with Close Combat. Aerial Ace has OHKO chances against Heracross, but the likelihood depends on Weavile's Attack; unless certain of it, fighting Heracross is not recommended. Snorlax 2-3HKOs with Body Slam, depending on Weavile's Defense; its Brick Break is only a 3HKO, however, so the matchup will be tendentially unfavourable, or turn out unfavourable if Body Slam paralyses. Roserade and Torterra can be 2HKOed with Ice Shard or Ice Beam. A healthy Weavile can also 2HKO Rapidash with Night Slash, though its Fire Blast can take up to 90% or thereabouts of Weavile's health, and will kill with a critical hit; Infernape is impossible to 2HKO and will just destroy Weavile with Focus Blast, as will Floatzel with Brick Break. Avoid Empoleon too, as its Metal Claw has high chances of 2HKOing, something Weavile is incapable of doing.
Elite Four Aaron (Pokémon League, Bug-type): Night Slash will 2HKO Dustox, and Ice Beam will OHKO Beautifly and 2HKO Vespiquen. Dustox's Bug Buzz is a 3HKO and Vespiquen's Attack Order is a 2HKO, so there are no risks involved unless one of the hits is a critical hit. Heracross and Drapion should not be fought, as they can overthrow Weavile easily, particularly Heracross.
Elite Four Bertha (Pokémon League, Ground-type): Since Quagsire's only attacking move is Dig, a 3HKO which takes two turns to execute, it provides perfect setup material. After three Swords Dances, all of Bertha's Pokémon are OHKOed: Night Slash for Quagsire, Whiscash and Hippowdon and Brick Break for Sudowoodo and Golem.
Elite Four Flint (Pokémon League, Fire-type): Rapidash must be avoided, it kills Weavile with Flare Blitz. Drifblim is 1-2HKOed by Night Slash, depending on Weavile's Attack as well as damage variation, but it is otherwise harmless; only Double Team could become a threat, if Weavile cannot hit and it Baton Passes to another Pokémon. Steelix can be Brick Break'd to death in four to five turns if Weavile can be healed, but a combination of Sunny Day and one Screech will turn its Fire Fang into an OHKO, and Weavile will have to bail out at that point. Brick Break 2HKOs Lopunny, which can only 3HKO with Fire Punch, unless it resorts to Charm; Infernape ruins Weavile with Mach Punch and its resistance to both of Weavile's STABs.
Elite Four Lucian (Pokémon League, Psychic-type): Mr. Mime, Girafarig and Alakazam get wrecked by Night Slash. Since Mr. Mime's strongest move is Thunderbolt, a 4-5HKO on average, Weavile can profit of the first three turns to Swords Dance; this allows it to also OHKO Bronzong and Medicham. If Mr. Mime puts up Reflect, Weavile needs to stall it out before beating the mime, otherwise its solo will be ruined.
Champion Cynthia (Pokémon League): Spiritomb's Silver Wind is a 3HKO, and once again offers Weavile a setup opportunity. At two Swords Dances Night Slash OHKOs Spiritomb, Milotic and Gastrodon, Ice Shard OHKOs Roserade and Garchomp, and Brick Break OHKOs Lucario, achieving a perfect solo.
Post-Game: Ice Shard is still underpowered, and Night Slash is also kind of underpowered. But more importantly, why nuzlocke further at all?
Gym #7 - Candice (Snowpoint City, Ice-type): Avoid the lead: Piloswine has Stone Edge, and can either one- or two-shot Sneasel before it can deal significant damage. Candice's Sneasel lacks Fighting coverage, so Sneasel can exploit it to put up two Swords Dances and then OHKO Sneasel and Abomasnow with Brick Break. If Abomasnow is sent out first, instead, Sneasel needs to switch out, otherwise it will be killed by Focus Blast. Whether Sneasel has set up or not, it can take on Froslass without problems, as it resists or is immune to all of Froslass' moves and can shrug off its evasion boosters, thanks to Faint Attack.
Cyrus (Galactic HQ): A Swords Dance against Sneasel is enough to OHKO all of Cyrus' team; Brick Break disposes of his Sneasel, whereas Ice Punch kills Crobat and Honchkrow. If Sneasel is outsped by Crobat, be careful of Supersonic: with a boosted Attack and its frail Defense, confusion recoil will hit Sneasel hard.
Saturn (Galactic HQ): The number of Pokémon Sneasel will be able to take on depends on how many Swords Dances it can set up. At +4 Attack, Toxicroak is OHKOed by Ice Punch; at +6, Bronzong is OHKOed by Faint Attack. Golbat can be OHKOed after a Swords Dance or 2HKOed without, preferably the former.
Mars and Jupiter (Spear Pillar, tag battle with rival): Both Mars and Jupiter lead with a Bronzor carrying Gyro Ball, which comes close to 2HKOing Weavile; if both of them use the move, Weavile may be killed in one hit. Once they are gone, the weasel may attempt to tackle the two Golbat, as it can take their hits fairly well and Ice Punch has a high chance of OHKOing each of them, which becomes a certainty with the NeverMeltIce. Moreover, while Purugly can be 2HKOed clean with Brick Break, Skuntank has Flamethrower and a small chance of 2HKOing Weavile, whose Ice Punch can only 3HKO. Unless Weavile has Dig, which does allow the 2HKO, it should preferably not be on the battlefield when Skuntank is out, and at any rate, Weavile is not the ideal Pokémon to use for most of this confrontation; if possible, keep it out.
Cyrus (Distortion World): Brick Break has a slim OHKO chance against Houndoom; Dig is more likely to OHKO it. Either way, a single Flamethrower cannot take Weavile down unless its Special Defense is below average, and Flamethrower rolls for high damage. Given that, Weavile may want to use Swords Dance on the first turn instead, then KO Houndoom next; Ice Punch will OHKO Crobat after a Swords Dance, and also OHKO Honchkrow for certain (chances are high even without a Swords Dance), whereas Cyrus' Weavile is OHKOed by Brick Break regardless. At least two Swords Dances are needed to hope for a Gyarados OHKO, instead; Gyarados' Intimidate will only allow a Weavile at three Swords Dances to kill for sure with Ice Punch, after the -1 Attack. Gyarados also holds the Quick Claw, and its Giga Impact deals up to about three quarters to Weavile, so only a healthy one should be fighting Gyarados.
Giratina (Distortion World): Weavile can 2HKO Giratina for certain with Ice Punch if it holds the NeverMeltIce. Its high Speed and Ghost resistance guarantee its survival through a Shadow Force; only a critical Dragon Claw can kill.
Gym #8 - Volkner (Sunyshore City, Electric-type): Weavile can take two Charge Beams from Jolteon even if the first gives it the Special Attack boost. As such, it can put up two Swords Dances and then OHKO all of Volkner's Pokémon with Ice Punch. If it knows Dig, only one Swords Dance is necessary.
Rival (Pokémon League): Weavile should not attempt to fight Staraptor, as its Intimidate will nullify Weavile's OHKO chances with Ice Punch. Aerial Ace has OHKO chances against Heracross, but the likelihood depends on Weavile's Attack; unless certain of it, fighting Heracross is not recommended. Snorlax 2-3HKOs with Body Slam, depending on Weavile's Defense; its Brick Break is only a 3HKO, however, so the matchup will be tendentially unfavourable, or turn out unfavourable if Body Slam paralyses. Roserade and Torterra are OHKOed easily with Ice Punch. A healthy Weavile can also 2HKO Rapidash with Night Slash, though its Fire Blast can take up to 90% or thereabouts of Weavile's health, and will kill with a critical hit; Infernape is impossible to 2HKO and will just destroy Weavile with Focus Blast, as will Floatzel with Brick Break. Avoid Empoleon too, as its Metal Claw has high chances of 2HKOing, something Weavile is incapable of doing.
Elite Four Aaron (Pokémon League, Bug-type): Ice Punch will OHKO Yanmega and Vespiquen. The move can only 2HKO Heracross and 3HKO Drapion, however, so Weavile can fight the former only with a prior Swords Dance and the latter only with two Swords Dances or its full HP, as X-Scissor will deal about as much damage, coming close to 2HKO range. At any rate, Weavile should not attempt to get past Scizor's Iron Head.
Elite Four Bertha (Pokémon League, Ground-type): Since Whiscash cannot even 2HKO Weavile, it provides perfect setup material. After a single Swords Dance, all of Bertha's Pokémon are OHKOed by Ice Punch.
Elite Four Flint (Pokémon League, Fire-type): Houndoom cannot OHKO with Flamethrower unless it is a critical hit, so Weavile should exploit the first turn to Swords Dance. Houndoom is OHKOed by Brick Break and, at +2 Attack, Flareon and Rapidash - otherwise unapproachable, as their Fire STABs can OHKO Weavile - are OHKOed by Night Slash. There is a high OHKO chance against Magmortar as well, but should it fail, its Flamethrower also has a small chance of OHKOing from full health; a damaged Weavile will not survive. Unfortunately, Infernape ruins Weavile's glorious Fire solo with Mach Punch and its resistance to both of Weavile's STABs.
Elite Four Lucian (Pokémon League, Psychic-type): Mr. Mime, Espeon and Alakazam get wrecked by Night Slash. Since Mr. Mime's strongest move is Thunderbolt, a 4-5HKO on average, Weavile can profit of the first two turns to Swords Dance; this allows it to also OHKO Bronzong with Night Slash and Gallade with Ice Punch. If Mr. Mime puts up Reflect, Weavile needs to stall it out before beating the mime, otherwise its solo will be ruined.
Champion Cynthia (Pokémon League): Spiritomb's Silver Wind is a 3HKO, and once again offers Weavile a setup opportunity. At two Swords Dances Ice Punch OHKOs Spiritomb, Roserade and Garchomp, Night Slash OHKOs Milotic, and Brick Break OHKOs Lucario, achieving a perfect solo.
Post-Game: Ice Punch and Night Slash are still kind of underpowered. But more importantly, why nuzlocke further at all?
Most Sneasel start off with a combination of Fury Swipes, Agility, Icy Wind, and either Faint Attack or Slash. Unfortunately, there is not much more in store for this line, as far as level-up moves go. The very low Special Attack makes special moves just plain unusable, and both Slash and Faint Attack are the best Weavile can get until it evolves. The best option is to evolve Sneasel at level 35 if Weavile is playing Platinum, so that it can learn Night Slash right after becoming a Weavile; the critical hit rate is "only" 12.5% in this generation when not boosted, but the STAB and base power are nice and will last for a good while, especially at this level. If playing Diamond or Pearl, Weavile is likely better off waiting, for reasons that will be explained shortly. At level 38, Sneasel gets Beat Up and Weavile gets Fling; neither move is really worthy of mention, since Weavile should already have good Dark STAB at this point. Metal Claw comes at level 42 for both Pokémon, and the last level-up move is Ice Shard for Sneasel and Dark Pulse for Weavile. This is a crucial point in favour of a delayed evolution in Diamond and Pearl, as Ice Shard is the only physical Ice move the line can get, and Weavile does not have access to it. Platinum is another story (thankfully), due to the Ice Punch tutor being available as soon as after reaching Pastoria, which is long before Sneasel even becomes available.
There is not much else to do with this line besides giving it a lot of TMs. Brick Break is excellent for coverage purposes, especially paired with Dark STAB; it gives near-perfect coverage to Weavile. Dig is also an option, thanks to the enhanced base power in this generation, if the team does not have anything else to counter Electric-types. Aerial Ace and X-Scissor are both good moves, but their coverage is outclassed by Ice and Dark respectively, so the TMs are likely best saved for a Pokémon that needs better moves more than Weavile does. Weavile that are stronger and more durable than average may run the Substitute and Focus Punch combo, but the vast majority of Weavile will not be able to use it.
A noteworthy move that Weavile gets through the Move Reminder is Nasty Plot. It actually makes special TMs such as Ice Beam and Focus Blast much more viable, and basically achieves the same coverage level as the physical variant, except with a higher base power for all moves. The point, however, is that Weavile also gets Swords Dance via TM, and that makes up for a much better option than any Special Attack boosting move in general, since its base Attack is almost three times as much as its Special Attack in its natural state.
The Platinum tutors are a major selling point for this line in the game: it gets Ice Punch for a handful of Shards, which is the only decent physical Ice move the line can learn. Diamond and Pearl players are, sadly, stuck with Sneasel's level-up Ice Shard, if they want any physical Ice move at all.
Recommended moveset: Swords Dance, Night Slash, Ice Punch [Platinum] / Ice Shard [Diamond and Pearl], Brick Break
Poison-types: Weavile is good at dealing hits, so its weaknesses should preferably be compensated defensively; Poison-types resist Fighting moves, and unlike Psychic- and Flying-types, they are not weak to any of the types Weavile is weak against. In fact, Weavile's typing is great to compensate Poison, dealing super effective damage to both Psychic and Ground.
Water-types: Though Water-types are generally welcome on most teams, they are more than necessary to supplement Weavile. Fire and Steel are only well covered by Water, and Weavile's Rock weakness can also be partly compensated with super effective damage that way.
Ground-types: Like Water-types, they work well against most of Weavile's weaknesses, also providing a welcome Rock resistance. They can be run either alongside Water-types or in their place, as their STAB is also good against Fire and Steel, which Water-types would otherwise cover for.
Physical tanks: Weavile's chronic Fighting weakness, as well as its other largely physical weaknesses, make its Defense look lower than it actually is. Regardless, the problem remains: Weavile will hardly be able to take a physical move even once fully evolved, and there is no way around designating a physical tank for the team. Choices are fairly limited, due to most good physical tanks having overlapping weaknesses, but some of the good ones are fairly common to find.
Minimum stats are calculated with 0 EVs, IVs of 0, and a hindering nature, if applicable.
Maximum stats are calculated with 252 EVs, IVs of 31, and a helpful nature, if applicable.
Sneasel Line Ratings
What Nature do I want? Adamant, definitely. Weavile is a physical sweeper, and cannot use its Special Attack to save its life. Failing that, Lonely and Naughty will also work, although the latter will make a much less welcome dent in its actually good defensive stat; Brave is also okay, as its Speed is high enough as is, and will probably not need further boosts to fight much of anything.
Which Ability do I want? Inner Focus and Keen Eye are both fairly situational on Sneasel, and Weavile only has Pressure. Whichever one Weavile gets does not really matter in the long run, as neither ability is very useful.
At what point in the game should I be evolved? Anywhere up to level 35 is the best option for Platinum, as it allows Weavile to access Night Slash without needing the Move Reminder for that. A later evolution is also fine, though, since Weavile will only need one more Heart Scale for its best level-up move. In general terms, evolve as soon as possible; Sneasel is frail, and Weavile has better chances of surviving untimely critical hits. However, if playing Diamond or Pearl, the story is different - the only sensible idea is to wait until level 49 for the evolution, as that is when Sneasel gets its literally only physical Ice move accessible in the game. Yes, its physical Ice coverage is just that bad.
How good is the Sneasel line in a Nuzlocke? Its stats are heavenly for a glass cannon, but it is crippled by lacking access to moves that have a powerful enough base power. The nifty coverage partially compensates for it, but with the double weakness to Fighting and all the other weaknesses to account for, using Weavile is often risky at best. However, if the player has good knowledge of the game and knows Weavile's enemies well, it becomes a powerful ally, especially for the ever-dreaded Champion's ace, which it can easily defeat in one punch.