Snorlax's main use in OU is to stop common sun sweepers, such as Volcarona. Thick Fat and great special bulk allow Snorlax to deal with numerous special attackers. Snorlax is unique in being able to take hits well while still being able to hit quite hard. Snorlax can also Pursuit trap, which is always useful. It must be understood, however, that none of this equates to Snorlax being a great Pokemon; it simply has a niche. While, in previous generations, fewer Pokemon could hit it hard, this generation shifted the metagame toward a more offensive one filled with threatening Fighting-types. The current metagame is too fast-paced for the once god-like CurseLax to achieve much of anything, and the prevalence of rain allows any Pokemon with a powerful Water STAB to rip Snorlax apart. Common sweepers, such as Dragonite, Latias, and Keldeo, can exploit Snorlax's abysmal Speed. If you stick to its strengths—that is, checking sun and special attackers in general—Snorlax should prove useful.
The main goal of this set is to function as what you might call a "utility check." With Choice Band-boosted attacks and high special bulk, Snorlax can combat sun teams effectively, boasting the ability to defeat or at the very least check Xatu, Volcarona, Venusaur, and Dugtrio—a common sun team core. With its great special bulk, Snorlax can also check Pokemon such as Latios and Latias that rely on special attacks to deal damage.
Snorlax has decent match-ups versus numerous Pursuit-weak Pokemon, such as Gengar, Latios, Starmie, and Celebi; Snorlax can switch into most of their moves and OHKO them with Pursuit, should they flee. Pursuit also helps in wearing down unsuspecting weather inducers, such as Politoed, Ninetales, and Abomasnow, that cannot do much damage back to Snorlax. Return is preferred for Snorlax's STAB due to its high Base Power, but Body Slam can spread paralysis, though the power drop from Return is significant. The remaining coverage moves are mainly to hit Steel-types. Fire Punch decimates Ferrothorn, Forretress, Jirachi, and Scizor that might switch in. The final move should be chosen based on what Pokemon you can afford to have wall Snorlax. Superpower is by far preferred, OHKOing Heatran, Tyranitar, Blissey, and Chansey. However, Wild Charge hits Tentacruel, Jellicent, Vaporeon, Slowbro, Politoed, and Skarmory hard. Keep in mind, however, that Skarmory can easily outspeed Snorlax and Roost to recover its HP while preventing Wild Charge from hitting it super effectively.Team Options & Additional Comments >>>
Two classic sets have all but disappeared from today's metagame: the famed CurseLax, and RestTalk Whirlwind. Neither of these sets are able to keep up with the fast-paced nature of BW OU. An attacking set with Expert Belt, Lum Berry, Chople Berry, or Leftovers over Choice Band can be viable, but the main issue of such a set is the power decrease; without Choice Band, Snorlax is too weak to be effective. A gimmicky set with Stockpile, Belly Drum, and ChestoRest has the potential to make Snorlax into a dangerous bulky sweeper, but is incredibly unrealistic to pull off. A set of Protect, Whirlwind, Body Slam, and Refresh is usable to spread paralysis and scout while staying free of status conditions. Three moves worthy of consideration are Fire Blast, which exploits Skarmory and Forretress's low Special Defense; Counter, which can hit unwary physical attackers back hard; and Rock Slide, which can OHKO even bulky Volcarona.
It must be emphasized that under no circumstances should you use Immunity or Gluttony over Thick Fat; Thick Fat is key to Snorlax's success. Without Thick Fat, Snorlax loses its main selling point as a check to sun teams, its only real niche in OU.
Checks and Counters
One of the best ways to deal with Snorlax is to pack a powerful Fighting-type such as Terrakion, Keldeo, Breloom, Lucario, or Conkeldurr. Terrakion and Lucario are preferred because they resist Snorlax's STAB, but all of them can at least threaten Snorlax once they manage to switch in. Snorlax can also be worn down through residual damage. Status is the best way of doing so, particularly Toxic and burn—Rotom-W, Jellicent, and Tentacruel are your best bets for inflicting such conditions. Entry hazards also limit the amount of time Snorlax will be able to switch into battle. Rain-boosted STAB Water-type attacks from Pokemon such as Choice Specs Keldeo and Rotom-W are capable 2HKOing Snorlax. Hammering Snorlax with strong physical attacks from Pokemon will also do the trick.
There are bulkier, more reliable counters for Snorlax. The most prominent of these is Skarmory, who cannot be 2HKOed by any move besides Wild Charge and can set up Spikes or stall with Roost. Another good counter is Jellicent, who also cannot be 2HKOed by any move besides Wild Charge and is immune to Normal-type attacks. Landorus-T, Hippowdon, and Gliscor are other Pokemon that work nicely, all of which are able to set up Stealth Rock and potentially inflict Snorlax with status. Snorlax is also vulnerable to being set up on by bulky setup sweepers, such as Latias and Dragonite. Overall, Snorlax isn't a difficult Pokemon to counter by any means, so it shouldn't be much trouble unless you are horrifically under-prepared for it.