Mega Altaria UU

Hydreigon @ Fightinium Z
Ability: Levitate
EVs: 4 Atk / 252 SpA / 252 Spe
Naive Nature
- Superpower
- Draco Meteor
- Dark Pulse
- Roost

Jirachi @ Leftovers
Ability: Serene Grace
EVs: 252 HP / 212 SpD / 44 Spe
Careful Nature
- Stealth Rock
- Wish
- Iron Head
- U-turn

Rotom-Wash @ Leftovers
Ability: Levitate
EVs: 252 HP / 168 Def / 88 Spe
Impish Nature
IVs: 0 Atk
- Volt Switch
- Hydro Pump
- Will-O-Wisp
- Pain Split

Altaria-Mega @ Altarianite
Ability: Natural Cure
Happiness: 0
EVs: 248 HP / 80 Def / 84 SpD / 96 Spe
Jolly Nature
- Dragon Dance
- Frustration
- Earthquake
- Roost

Nihilego @ Choice Scarf
Ability: Beast Boost
Happiness: 0
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Sludge Wave
- Power Gem
- Thunderbolt
- Hidden Power [Ice]

Mandibuzz @ Rocky Helmet
Ability: Overcoat
Happiness: 0
EVs: 240 HP / 212 SpD / 56 Spe
Careful Nature
- Roost
- Defog
- Knock Off
- Taunt