JCM here, welcome to my RMT! I hope you like this, as I worked hard on it.
Snover @ Eviolite | Snow Warning
Calm | 248 HP / 8 SAtk / 252 SDef
Protect | Leech Seed | Blizzard | Toxic
Well, Snover is actually needed in a Hail team to summon Hail with his Ability. People usually go on with the same crap; Snover is dead-weight on a team, he's a waste of moveslot, and blah blah. And I'll tell you what, I thought the same thing at the beginning. But his power (or resistance) lies in his horrid typing, which can grant him some useful resistances and STABs. Special Snover is the closest you'll come to walling, so I use him to counter RD Ludicolo and Special Samurott. Protect allows him to scout moves, and makes switching easier against Choice-locked Pokemon, such as Emboar or Sawk. Leech Seed allows you to hamper some Pokemon that would switch in to counter you, such as Emboar, mentioned for the second time here. With the Hail damage, it takes away a lot of HP. Blizzard is the strongest move on this moveset, but it doesn't even OHKO Neutral Golurk xD. Nonetheless, it's still strong, though. Toxic is really useful here because I can Toxic common switch-ins, such as Emboar, who always tries to switch-in on me. . The EVs have been invested to be able to take most Special hits, and so was the Nature. 8 SAtk ensures me to OHKO one Pokemon with Blizzard after Hail damage, I forgot who it was.
Rotom-Frost @ Choice Scarf | Levitate
Timid | 4 Def / 252 SAtk / 252 Spd
Blizzard | Thunderbolt | Volt Switch | Trick
After my team had 3 losses in a row, I went to Smogon NU Irc to see what was wrong with my team. Some Smogonites told me to get rid of Vanilluxe, and especially put Scarf. While SubSplit is the superior set, Scarf set works better on this team. Scarf allows me to outspeed +2 Gorebyss, who is always a threat, and allows me to revenge kill. Blizzard is the move I use the most. BlizzSpamming is fun and wrecks the opponent's team once Sawk takes care of Probopass and Bastiodon. Thunderbolt gets a hard hit on Water-types, and completes the BoltBeam combo on which Rotom-F gets STAB. Volt Switch makes predicting much more easier, and allows me to get a hard hit on some stuff that can threaten me. It also keeps the momentum going, which is very important. Trick can screw some Pokemon that can screw me up, including Duosion and Musharna. Scarf allows me to outspeed key threats and OHKO, while EVs and Nature maximise Speed and give a lot of SAtk.
Duosion @ Eviolite | Magic Guard
Bold | 252 HP / 252 Def / 4 SDef
Psychic | Calm Mind | Signal Beam | Recover
Duosion is like, the new Musharna. Literally. This thing has huge bulk with Eviolite, and can be invincible if you can get a couple of Calm Minds under your belt. He's my premier Band Sawk. Magic Guard is what makes this thing strong. It can make Duosion a great Status absorber, except for Sleep and Paralysis. The funniest thing is that when Alo or any other wall Poisons you, Amoonguss cannot put you to Sleep, so it can't cut your sweep. Someone could tell me: ''JCM, how can Duosion be a Sawk counter if the Sawk carries Payback?''. I have two answers to that. 1) Nobody uses Payback Sawk anymore. 2) It's a 3HKO. Duosion has time to use one CM, and then get the KO and use Recover. On to the moves. Psychic is STAB and checks a lot of things in NU. Calm Mind boost my average SDef to very high levels, making Duosion very bulky on both sides. Signal Beam hits Dark-types and other Psychic-types for big damage. It can 2HKO Absol, who does about 55% in return with Night Slash. I can also get the guaranteed OHKO at +1. Pursuit from Skuntank, if I choose to stay in, doesn't get the 3HKO, which is really funny. Sadly, I can't do much in return, getting the 3HKO at +1, which is pretty pathetic if you ask me. Recover is what Duosion has over Musharna in this Hail infested metagame, as Hail cuts by 50% Moonlight's recovery. It makes Duosion very hard to take down at +1 or +2. EVs and Nature maximise Physical bulk, as CM can turn me into a Special wall as well too. Item is kind of mandatory...
Glaceon @ Choice Specs | Ice Body
Modest | 4 HP / 252 SAtk / 252 Spd
Frost Breath | Blizzard | Hidden Power [Grass] | Shadow Ball
This thing. This thing right here is hands-down the MVP of my team. Specs Glaceon hits like a monster truck, and gets the 2HKO on most things that even resist, except Regice (Screw you.). Blizzard is my primary move, and hits so hard that it does over 70% to Alomomola. Frost Breath is very useful. It can get a hard hit on Musharna and Duosion, after they used Calm Mind, as critical hits ignore Defense boosts. It OHKO's Duosion, and get the 2HKO on Musharna, iirc. HP [Grass] is hardly used, as it's a bad move to be locked in, but I usually use it to beat Specially Defensive Wartortle, and sometimes Alo when I don't want to waste a Blizzard PP. Shadow Ball is my least used move, but at least it gets a hit on bulky Ghosts like Misdreavus. Choice Specs make me hit super hard, while EVs and Nature maximise SAtk.
Sawk (M) @ Choice Band | Mold Breaker
Adamant | 4 HP / 252 Atk / 252 Spd
Close Combat | Earthquake | Stone Edge | Ice Punch
Band Sawk is like, the glue on my team. He hits like a truck, and usually keeps Stealth Rock out of the field. Close Combat is my STAB move, and hits like a fire truck. Earthquake and Stone Edge make the EdgeQuake combo, and gives me a lot of coverage. Ice Punch allows me to hit predicted Golurk switch-ins and OHKO, who is otherwise an enemy to this set. Choice Band makes me hit super hard and turns me into a fearsome wallbreaker, while EVs and Nature maximise Attack.
Regirock (M) @ Rocky Helmet | Clear Body
Adamant | 252 HP / 252 Atk / 4 Def
Stealth Rock | Rock Slide | Drain Punch | Thunder Wave
The only Defensive Pokemon on my team. Well, semi-defensive. Stealth Rocks are very important in NU, as they can decimate some threats to my team, such as the annoying Specially Defensive Articuno. Rock Slide hits hard with max Attack, and can hit some opposing Hail Pokemon, such as Rotom-F or Glaceon. Drain Punch makes me hit Normal-Pokemon for super-effective damage, and makes me regain some health. Thunder Wave is very helpful for this team, as it can help Glaceon sweep. Rocky Helmet is extremely useful, as after Hail damage, it can leave Cinccino with 2% after it uses Tail Slap. EVs and Nature make me hit harder, as my Defense is already sky-high. Regirock acts as a great Physical wall, as a Hail counter and as a bird counter.