My 1st Team (X/Y)

[HeNRiQueZ1M]

Gyarados
Nature: Adamant
Ability: Intimidate
Moveset:
- Earthquake
- Stone Edge
- Dragon Dance
- Waterfall
EV: 252 Attack - 252 Speed - 4 Def
Item: Gyaradosite

Umbreon
Nature: Calm
Ability: Synchronize
Moveset:
- Taunt
- Confuse Ray
- Protect
- Wish
EV: 252 HP - 252 SpDef - 4 Def
Item: Leftovers

Dusclops
Nature: Bold
Ability: Pressure
Moveset:
- Will-O-Wisp
- Night Shade
- Pain Split
- Confuse Ray
EV: 252 Def - 252 SpDef - 4 HP
Item: Eviolite

Greninja
Nature: Modest
Ability: Protean
Moveset:
- Surf
- Ice Beam
- Hidden Power (Fire)
- Extrasensory
EV: 252 SpAtk - 252 Speed - 4 HP
Item: Life Orb

Aegislash
Nature: Adamant
Ability: Stance Change
Moveset:
- King Shield
- Sacred Sword
- Sword Dance
- Shadow Sneak
EV: 252 Atk - 252 Speed - 4 HP
Item: ???

Magnezone
Nature: Modest
Ability: Magnet Pull
Moveset:
- Thunderbolt
- Flash Cannon
- Hidden Power (Fire)
- Substitute
EV: 252 SpAtk - 252 Speed - 4 HP
Item: Air Balloon

Suggestions Please o/

 

[wolf]

I'd personally use Jolly Nature on Gyarados so you can outrun stuff like Mega Gengar, Jolteon, and Scarf Politoed. The drop in power is mitigated by its Mega Evo.

Umbreon is too slow to take advantage of Taunt, and even on slower Pokemon like walls, it can't do much to them. Replace it with Foul Play so it has an attacking move, and therefore won't be Taunt bait for others. Because of Foul Play being a physical attack, change Umbreon's Nature to Careful. Confuse Ray is unreliable and I suggest replacing it for Heal Bell or Toxic, both of which provide much better support. Most of your team is pretty vulnerable to status, especially Dusclops, so I highly recommend Heal Bell. Toxic works well with Wish + Protect and can help Umbreon deal more damage, though. I also want to add that Blissey (https://www.smogon.com/forums/threads/qc-ready-2-3-blissey.3490555/) and Sylveon (https://www.smogon.com/forums/threads/qc-ready-0-3-sylveon.3490805/) outclass Umbreon as a Wish passer due to being more competent special walls and having better typing. As a result, replace Umbreon with one of them. Sylveon has a nice immunity to Dragon attacks, and that would be helpful.

Move the SDef EVs on Dusclops to HP. Dusclops has very low HP, and the HP EVs try to help improve it. Otherwise, it looks fine, but Dusclops is a very, very mediocre Pokemon in general. It really only works well on full stall teams that don't mind it not doing any immediate damage. Additionally, you already have Aegislash as your team's Ghost in the first place, so I don't really see the point in having Dusclops. It just slows down the team, and at least Umbreon can provide Wish support, y'know? As such, I recommend that you replace it with something that will benefit your team more. Maybe a Choice Scarf or priority user to help with set-up sweepers. Either that, or a Stealth Rock setter, especially since you have plenty of Ghosts to block Rapid Spin. I might come back with more suggestions on this.

On Greninja, Replace Modest Nature with Timid. With Modest, it's outrun by looooads of stuff, including Starmie, Alakazam, Mega Lucario, Gengar, Lati@s, Terrakion, Mega Absol, +1 Adamant Dragonite, Infernape, etc.

Swapping the Spd EVs with HP on Aegislash would help a lot, especially with taking hits before it uses Sacred Sword or Swords Dance. Aegislash is slow as heck anyway. Leftovers or Life Orb would be best for it, depending on your preference: survivability or power.

Consider Specs Magnezone because it has a more immediate offensive presence and can beat Aegislash more easily (https://www.smogon.com/forums/threads/qc-ready-0-3-magnezone.3490831/).

 

[PlatinumDude]

Building on to Wolfare's suggestion, Aegislash shouldn't use Speed EVs unless it's using Autotomize. It will want to take a hit in Shield Forme before turning into Blade Forme to attack. For your Aegislash set, use 252 HP/252 Atk/4 Def. If you still want Aegislash to run some Speed, here are some sets that can do that:
-Autotomize
-Swords Dance
-Shadow Claw
-Sacred Sword/Iron Head
Nature: Adamant
EVs: 88 HP/252 Atk/168 Spe
Item: Leftovers

or
-Autotomize
-Shadow Ball
-Hidden Power (Ice)
-Sacred Sword/Iron Head
Nature: Rash
EVs: 88 Atk/252 SAtk/168 Spe
Item: Life Orb