Abomasnow (M) @ Expert Belt
Trait: Snow Warning
EVs: 252 Atk / 112 SAtk / 144 Spd
- Wood Hammer
- Hidden Power [Fire]
- Ice Shard
Role: Weather Support
What It Does: Abomasnow brings the big chill. It's good at what it does...because it's the only thing that does it! But more seriously, Abomasnow's stats wouldn't seem to indicate that it's a particularly great pokemon, which is true. However, Abomasnow is outstanding at filling particularly niches and, if used correctly, can be a great addition to a team. This set can be used in two ways - either as a way to screw with opposing weather teams, or to set up a dedicated hail team. Its typing and coverage allow it to most importantly destroy other weather starters. This speed investment outspeeds and OHKOs every standard Politoed barring Choice, and every standard Tyranitar barring mixed variants. Earthquake also does a number on Ninetales on the switch, OHKOing many variants after Stealth Rock. While this is useful, it's not all Abomasnow can do. Ice/Grass typing sticks you with many weaknesses, but useful resistances to common BoltBeam coverage, as well as Ground and Water. This allows you to wall threats like Starmie, tank Volt Switches from Rotom, and much more. The coverage moves allow you to dent many common switches. EQ hits things like Jirachi, Heatran and Tentacruel. HP Fire handles Scizor and Forretress and 2HKOs Ferrothorn. Finally, Ice Shard allows you to revenge many potent attackers in the current metagame with some prior damage - think Dragonite, Garchomp, Salamence, all three Therians, and Latios.
Good Teammates: This depends on whether you are using a dedicated hail team, or simply screwing with your opponents. If it's the latter, then Abomasnow is fairly independent. If you are using a hail team, then look for pokemon who can use the hail to their advantage. Things like Kyurem or Kyurem-B love a 100% accurate Blizzard to spam, and defensively, pokemon like Stallrein can wreak havoc. No matter what, however, Abomasnow needs Rapid Spin support, being weak to Stealth Rock and vulnerable to Spikes and Toxic Spikes. Good spinners to partner with Abomasnow include Tentacruel, who patches up Fire and Fighting weaknesses, as well as Donphan, who can tank physical hits.
Edit (Credit @Milos): Another great teammate is Heatran, who absorbs fire attacks and Will-o-Wisp which screw Abomasnow, while setting up Stealth Rock and providing some offensive presence. Heatran also shuts down sun teams, which Abomasnow has the most trouble with.
What Counters It: Many things counter Abomasnow, including some of the things it's designed to handle, as this set is much more about picking your spots and punishing switch-ins than facing opponents straight up. Be sure to scout Politoed and Tyranitar beforehand to be safe - Abomasnow can't take a Focus Blast or Fire Blast. Chansey and Blissey don't enjoy taking a Wood Hammer, but can heal off the damage, and the recoil will kill Abomasnow eventually. CM Latias can shrug off Ice Shard with recover and boost up to kill Abomasnow. Scarfed pokemon like Keldeo finish off Abomasnow with their speed, but often dislike taking hits on the switch. Fighting types like Breloom, Infernape and Terrakion hurt, but dislike Ice Shard and EQ, respectively. Finally, Volcarona sets up all over this thing. Again, though, it's all about whether any of these opponents can get in safely, which is often not the case.
Any Additional Info: This set is not something you can just slap on a team! As mentioned previously, Abomasnow has too many weaknesses to be viable anywhere. It's outstanding at very particular roles, but don't try to make it something it isn't.