I could do few changes in my opinion:
I like Greninja with U-turn for scounting, it's very useful. Life Orb is great for him too. Naive/Hasty cause your Greninja isn't a tank, so don't worry with defenses, and you can do a little bit more damage with U-turn.
Greninja @Life Orb
Ability: Protean
Naive Nature (+Spe, -Sdef) / Hasty Nature (+Spe, -Def)
EVs: 252 Spe, 252 Satk, 4 Hp
- Hydro Pump
- Dark Pusle
- Ice Beam
- U-turn
Charizard X is physical, and Y is Special, go for Charizard Y, also you don't need Sunny Day with his ability, go for Roost instead.
Mega Charizar Y @Charizardite Y
Ability: Drought
Timid Nature (+Spe, -Atk)
EVs: 252 Spe, 252 Satk, 4 Hp
- Fire Blast
- Solar Beam
- Dragon Pulse
- Roost
Ferrothorn is awsome and he can stall against special attacks too. Relaxed Nature is better for your Gyro Ball and Stealth Rocks are so painful.
Ferrothorn @Leftovers
Ability: Iron Barbs
Relaxed Nature (+Def, -Spe)
EVs: 252 Hp, 128 Def, 128 Sdef
- Gyro Ball
- Power Whip
- Stealth Rocks
- Leech Seed
If you want a good special wall go for Sylveon or Florges, not Auroros.
Sylveon @Lum Berry
Ability: Pixilate
Calm Nature (+Sdef, -Atk)
EVs: 252 Hp, 252 Sdef, 4 Satk
- Hyper Voice
- Wish
- Heal Bell
- Toxic
Toxicroak isn't that good without a synergy for him, I guess Lucario could be a good replacement here.
Lucario @Stirus Berry
Ability: Justified
Jolly Nature (+Spe, -Satk)
EVs: 252 Spe, 252 Atk, 4 Hp
- Sword Dance
- Bullet Punch
- Close Combat
- Earthquake
If you like Golurk, go for him! Brave Nature is for Gyro Ball after Hammer Arm, but Stone Edge and Adamant Nature are good options too.
Golurk @Expert Belt
Ability: Iron Fist
Brave Nature (+Atk, -Spe)
EVs: 252 Hp, 252 Atk, 4 Def
- Earthquake
- Shadow Punch
- Hammer Arm
- Gyro Ball
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That's it, just my opinion. Good luck with your team!!