Battle Spot Doubles - Mamoswine & Friends

[BlazeVGC]

This is a new team that I have built yesterday. My current record on Showdown with this team is 12-3.

Mamoswine @ Choice Scarf
Ability: Thick Fat
Level: 50
EVs: 36 HP / 100 Atk / 120 Def / 252 Spe
Impish Nature
- Icicle Crash
- Rock Slide
- Earthquake
- Superpower

Mamoswine is used to deal with both genies, but also great for flying types.
The EV spread is used for these calculations:

100 Atk Mamoswine Icicle Crash vs. 4 HP / 0 Def Thundurus: 174-206 (112.2 - 132.9%) -- guaranteed OHKO

-1 100 Atk Mamoswine Icicle Crash vs. 4 HP / 0 Def Landorus-T: 192-228 (116.3 - 138.1%) -- guaranteed OHKO

Rotom-Heat @ Sitrus Berry
Ability: Levitate
Level: 50
EVs: 252 HP / 4 Def / 108 SpA / 4 SpD / 140 Spe
Modest Nature
IVs: 0 Atk
- Will-O-Wisp
- Overheat
- Thunderbolt
- Protect

I decided to throw on Rotom because he is a bulky Pokemon, that also has access to will-o-wisp . I picked Rotom-H because I knew a water type that I would throw on later.
The EV spread is used for these calculations:

60 SpA Rotom-W Hydro Pump vs. 252 HP / 4 SpD Rotom-H: 132-156 (84 - 99.3%) -- guaranteed 2HKO after Sitrus Berry recovery

108+ SpA Rotom-H Overheat vs. 252 HP / 4 SpD Amoonguss: 222-264 (100.4 - 119.4%) -- guaranteed OHKO

108+ SpA Rotom-H Thunderbolt vs. 0 HP / 4 SpD Mega Charizard Y: 116-138 (75.8 - 90.1%) -- guaranteed 2HKO

Ferrothorn @ Rocky Helmet
Ability: Iron Barbs
Level: 50
EVs: 252 HP / 204 Atk / 52 SpD
Brave Nature
IVs: 0 Spe
- Power Whip
- Gyro Ball
- Leech Seed
- Protect

I decided now to continue the Fire/Water/Grass core. I added Ferrothorn mainly do to his dual typing making it able to hit Rotom-W and other water types, as well as Fairy types.
The EV spread is used for these calculations:

204+ Atk Ferrothorn Gyro Ball (115 BP) vs. 4 HP / 0 Def Mega Gardevoir: 236-278 (163.8 - 193%) -- guaranteed OHKO

204+ Atk Ferrothorn Power Whip vs. 252 HP / 100+ Def Suicune: 132-156 (63.7 - 75.3%) -- guaranteed 2HKO after Sitrus Berry recovery

Suicune @ Leftovers
Ability: Pressure
Level: 50
EVs: 252 HP / 100 Def / 100 SpA / 52 SpD / 4 Spe
Bold Nature
IVs: 0 Atk
- Scald
- Ice Beam
- Tailwind
- Protect

The last of the F/W/G core was Suicune. Suicune is decently bulky and can take multiple hits from Amoonguss and can help against fire types.
The EV spread is used for these calculations:

252 SpA Amoonguss Energy Ball vs. 252 HP / 52 SpD Suicune: 102-120 (49.2 - 57.9%) -- 46.1% chance to 2HKO after Leftovers recovery

100 SpA Suicune Scald vs. 4 HP / 0 SpD Heatran: 90-108 (53.8 - 64.6%) -- guaranteed 2HKO after Leftovers recovery

Hydreigon @ Life Orb
Ability: Levitate
Level: 50
EVs: 4 HP / 252 SpA / 252 Spe
Serious Nature
IVs: 0 Atk
- Draco Meteor
- Dark Pulse
- Fire Blast
- Protect

I already had Ferrothorn so I thought I might as well add Steel/Dragon/Fairy Core. This core was also great because There are many other Dragon, Steel and Fairy Types in this metagame, and this core can counter all. Hydreigon was mainly used for Heatran, but can 2HKO Cressalia.
The EV spread is used for these calculations:

252+ SpA Life Orb Hydreigon Earth Power vs. 252 HP / 252 SpD Heatran: 218-260 (110.1 - 131.3%) -- guaranteed OHKO

252+ SpA Life Orb Hydreigon Dark Pulse vs. 220 HP / 92+ SpD Cresselia: 133-156 (59.6 - 69.9%) -- guaranteed 2HKO

Gardevoir-Mega @ Gardevoirite
Ability: Pixilate
Level: 50
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Hyper Voice
- Shadow Ball
- Psychic
- Protect


Now lastly I needed a Fairy. I also needed a Mega so I had a choice between Gardevoir and Mawile. I opted for Gardevoir because of her moveset which was important in many matches.
The EV spread is used for these calculations:

252 SpA Mega Gardevoir Moonblast vs. 4 HP / 0 SpD Hydreigon: 424-504 (252.3 - 300%) -- guaranteed OHKO

252 SpA Mega Gardevoir Moonblast vs. 0 HP / 4 SpD Garchomp: 218-260 (119.1 - 142%) -- guaranteed OHKO

That's my team and I hope you guys can help to improve it even more!