Team Building Help!

[Barbarian]

Hello everyone! Need some help in regards of team building, item equipping, movesets and what pokémon to use in each team to create good synergy. Just so you all know, I've only recently (past month) gotten into competitive battling and training my pokémon to their potential. Feel free to recommend me new pokémon to use!

These are the pokémon I have EV trained so far:

Charizard Shiny (F) @ Mega X
Nature Adamant
Ability Blaze
6 IV ~ EV 252 Attack / 252 Speed / 4 Defense
Moveset Flare Blitz / Outrage / Flamethrower / Dragon Dance

Tyranitar (F) @ ???
Nature Adamant
Ability Sand Steam
6 IV ~ EV 252 Attack / 252 Speed / 4 HP
Moveset Crunch / Dragon Dance / Stone Edge / Earthquake

Greninja Shiny (M) @ ???
Nature Timid
Ability Protean
6 IV ~ EV 252 Speed / 252 Sp. Attack / 4 HP
Moveset Dark Pulse / Grass Knot / Ice Beam / Scald

Dragonite (F) @ ??? <— or Dragon Plate?
Nature Adamant
Ability Multiscale
6 IV ~ EV 252 Attack / 252 Speed / 4 Defense
Moveset Extreme Speed / Dragon Dance / Outrage / Dragon Rush

Reuniclus Shiny (F) @ Life Orb
Nature Quiet
Ability Magic Guard
6 IV ~ EV 252 HP / 252 Sp. Attack / 4 Defense
Moveset Trick Room / Psychic / Focus Blast / Shadow Ball

Togekiss (F) @ ???
Nature Modest
Ability Serene Grace
6 IV ~ EV 252 Sp. Attack / 252 Speed / 4 Defense
Moveset Air Slash / Roost / Aura Sphere / Toxic

Togekiss Shiny (F) @ ???
Nature Modest
Ability Serene Grace
6 IV ~ EV 252 Sp. Attack / 252 Speed / 4 Defense
Moveset Air Slash / Roost / Aura Sphere / Defog

Charizard (M) @ Mega Y
Nature Modest
Ability Blaze
6 IV ~ EV 252 Sp. Attack / 252 Speed / 4 Defense
Moveset Flamethrower / Solar Beam / Dragon Pulse / ???

Typhlosion Shiny (F) @ ??? <— or Rocky Helmet?
Nature Timid
Ability Blaze
6 IV ~ EV 252 Sp. Attack / 252 Speed / 4 Defense
Moveset Eruption / ??? / ??? / ???

Garchomp (F) @ Garchompite
Nature Adamant
Ability Rough Skin
6 IV ~ EV 252 Attack / 252 Speed / 4 HP
Moveset Earthquake / Dragon Rush / Rock Slide / Flamethrower

Latios (M) @ ??? <— or Latiosite when it's released
Nature Timid
Ability Levitate
6 IV ~ EV 252 Sp. Attack / 252 Speed / 4 Defense
Moveset Psychic / Recover / Dragon Dance / Surf or Ice Beam

Ampharos Shiny (F) @ Ampharosite <— possible Dragon Tank?
Nature Modest
Ability Plus
6 IV ~ EV 252 Sp. Attack / 252 HP / 4 Defense
Moveset Dragon Pulse / Lightscreen / Confuse Ray / Thunder

Milotic (F) @ ???
Nature Bold
Ability Marvel Scale
6 IV ~ EV 252 HP / 252 Defense / 4 Sp. Defense
Moveset Ice Beam / Recover / Scald / Toxic

Mawile Shiny (F) @ Mawalite
Nature Adamant
Ability Sheer Force
6 IV ~ EV 252 HP / 252 Attack / 4 Defense
Moveset Iron Head / Swords Dance / Sucker Punch / Play Rough

Manectric (F) @ Manectite
Nature Timid
Ability Static
6 IV ~ EV 252 Sp. Attack / 252 Speed / 4 HP
Moveset Thunderbolt / Flamethrower / Volt Switch / Signal Beam

Arcanine (F) @ ???
Nature Jolly
Ability Intimidate
6 IV ~ EV 252 Attack / 252 Speed / 4 HP
Moveset Extreme Speed / Flare Blitz / Wild Charge / Close Combat

Blastoise (M) @ ???
Nature Bold
Ability Rain Dish
6 IV ~ EV 252 Sp. Attack / 252 HP / 4 Sp. Defense
Moveset Rapid Spin / Scald / Dragon Tail / Toxic

Xatu (F) @ Light Clay
Nature Timid
Ability Magic Bounce
6 IV ~ EV 252 HP / 252 Speed / 4 Defense
Moveset Future Sight / Wish / Reflect / Light Screen or U Turn

I'll be training also a Mew, Blissey, Mega Lucario, Absol, Blaziken and Amaura. Note also that the pokémon who can mega evolve and have @ ??? by their name means that I don't want to ideally mega them. Thank you!

 

[PlatinumDude]

You have too many Mega Pokemon. You do realize you can only Mega Evolve 1 Pokemon per battle, right? It's better for you to use 1 Mega Pokemon on the team in the end.

Charizard X should use physical moves only to take better advantage of Tough Claws:
-Dragon Dance
-Flare Blitz/Fire Punch
-Dragon Claw/Outrage
-Earthquake/Roost/Swords Dance
Nature: Jolly/Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Charizardite X
Ability: Blaze

or
-Fire Punch/Earthquake
-Dragon Tail
-Will-o-Wisp
-Roost
Nature: Jolly
EVs: 248 HP/84 SDef/176 Spe
Item: Charizardite X
Ability: Blaze

Dragon Dance Tyranitar is only good in its Mega form, since it actually has a better Speed to use with the move. It must also use a Jolly nature as well. However, since your Mega slot is already taken by Charizard, a Rapid Spinner or Defogger is a better fit on the team, to clear away the entry hazards that Charizard is susceptible to:
Starmie:
-Hydro Pump/Surf
-Thunderbolt/Psyshock
-Ice Beam
-Rapid Spin
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Leftovers/Life Orb
Ability: Natural Cure

or
-Scald
-Rapid Spin
-Psyshock/Ice Beam/Thunderbolt
-Recover
Nature: Timid
EVs: 248 HP/32 Def/4 SAtk/224 Spe
Item: Leftovers
Ability: Natural Cure

Excadrill:
-Earthquake
-Rock Slide/Iron Head
-Rapid Spin
-Swords Dance/Stealth Rock
Nature: Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Leftovers/Air Balloon/Chople Berry
Ability: Mold Breaker

or
-Earthquake
-Iron Head
-Rock Slide
-Rapid Spin
Nature: Adamant/Jolly
EVs: 120 HP/136 Atk/252 SDef (Adamant) or 252 Atk/4 Def/252 Spe (Jolly)
Item: Assault Vest (Adamant)/Choice Scarf (Jolly)
Ability: Mold Breaker

Mandibuzz:
-Foul Play
-Roost
-Taunt/Whirlwind
-Defog/Toxic/Knock Off
Nature: Bold/Impish
EVs: 248 HP/216 Def/44 SDef
Item: Leftovers
Ability: Overcoat

Crobat:
-Brave Bird
-Defog
-Roost
-Taunt/Toxic
Nature: Jolly
EVs: 168 HP/136 Atk/4 SDef/200 Spe
Item: Black Sludge
Ability: Infiltrator

Tentacruel:
-Scald
-Sludge Bomb
-Rapid Spin
-Toxic/Knock Off
Nature: Bold
EVs: 252 HP/224 Def/32 Spe
Item: Black Sludge
Ability: Liquid Ooze

Scald only sees use on defensive Pokemon. Greninja appreciates the greater power that Hydro Pump (and even Surf) have:
-Hydro Pump/Surf
-Ice Beam/Dark Pulse
-Extrasensory/Dark Pulse
-U-turn/Hidden Power (Grass/Fire)/Grass Knot
Nature: Naive/Timid
EVs: 4 Atk/252 SAtk/252 Spe
Item: Life Orb/Expert Belt
Ability: Protean

or
-Spikes
-Hydro Pump/Surf
-Ice Beam
-U-turn/Extrasensory
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Life Orb/Focus Sash

You already have Charizard X, so I don't think you need Charizard Y at this point.

Mega Garchomp only sees use on sand teams; outside of sandstorm, Sand Force is useless:
-Swords Dance
-Outrage/Dragon Claw
-Earthquake
-Fire Fang/Stone Edge
Nature: Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Lum Berry/Yache Berry

or
-Outrage
-Earthquake
-Fire Fang/Stone Edge/Fire Blast
-Dragon Claw/Dual Chop
Nature: Jolly/Naive
EVs: 4 HP/252 Atk/252 Spe
Item: Choice Band/Choice Scarf

or
-Stealth Rock
-Outrage/Dragon Claw
-Earthquake
-Swords Dance/Fire Blast
Nature: Jolly/Naive
EVs: 4 HP/252 Atk/252 Spe
Item: Lum Berry/Focus Sash

Dragonite is seriously lacking in coverage here. Dragon Rush is too inaccurate to be worth bothering as a STAB move:
-Dragon Dance
-Outrage/Dragon Claw
-Extreme Speed
-Earthquake/Fire Punch/Thunder Punch
Nature: Adamant
EVs: 24 HP/252 Atk/232 Spe
Item: Lum Berry/Weakness Policy
Ability: Multiscale

or
-Outrage
-Extreme Speed
-Earthquake
-Fire Punch/Thunder Punch/Dragon Claw
Nature: Adamant
EVs: 252 Atk/4 SDef/252 Spe
Item: Choice Band
Ability: Multiscale

Togekiss is well-known for its para-flinch shenanigans, so paralysis is the preferred status condition for Togekiss to use:
-Thunder Wave/Nasty Plot
-Air Slash
-Dazzling Gleam/Defog/Aura Sphere
-Roost
Nature: Calm
EVs: 248 HP/8 SAtk/252 SDef
Item: Leftovers
Ability: Serene Grace

or
-Nasty Plot
-Dazzling Gleam
-Air Slash
-Flamethrower/Aura Sphere/Roost
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Leftovers/Life Orb
Ability: Serene Grace

I doubt Typhlosion's effectiveness in standard play. Sure, Eruption + Choice Scarf gives it a niche, but that's still not enough. Having Charizard as your Fire Pokemon is enough.

Mawile should look something like this:
-Play Rough
-Sucker Punch
-Fire Fang/Iron Head/Swords Dance
-Swords Dance/Substitute
Nature: Adamant
EVs: 132 HP/252 Atk/124 Spe
Item: Mawilite
Ability: Intimidate

Latios has better coverage options to use. Ice Beam is redundant with its Dragon STAB, which Latios lacks. Sure, Fairies are immune to Dragon, but having a Dragon STAB is good. And from what I've read, Mega Lati@s isn't that good, but time will tell:
-Draco Meteor
-Psyshock
-Surf/Hidden Power (Fire)/Earthquake
-Recover/Defog
Nature: Timid/Hasty
EVs: 4 HP/252 SAtk/252 Spe
Item: Life Orb

or
-Draco Meteor
-Psyshock
-Surf/Hidden Power (Fire)
-Trick/Hidden Power (Fire)
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Choice Specs/Choice Scarf

Ampharos has a better support option in Heal Bell to cure the team of status. Confuse Ray is unreliable, as the opponent can switch to cure the confusion. It also makes a good user of RestTalk:
-Rest
-Sleep Talk
-Volt Switch
-Dragon Pulse
Nature: Modest
EVs: 252 HP/44 SAtk/192 SDef/20 Spe
Item: Ampharosite
Ability: Static

or
-Volt Switch
-Dragon Pulse
-Focus Blast
-Thunderbolt/Discharge/Heal Bell
Nature: Modest
EVs: 236 HP/252 SAtk/20 Spe
Item: Ampharosite
Ability: Static

Even though the Hidden Power nerf hurt Manectric, Hidden Power is still the preferred coverage option for it:
-Thunderbolt
-Volt Switch
-Overheat
-Hidden Power (Ice)
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Manectite
Ability: Lightning Rod

I also doubt Arcanine's viability. Stick to Charizard.

Blastoise is only good in its Mega form. For better defensive Rapid Spin/Defog users, see above.

Xatu isn't that reliable as it was in Gen V. Future Sight is a terrible attack, as it only hits the opponent 2 turns after it's used, and this gives Dark Pokemon plenty of time to switch in and be immune to the attack if it hits. Just stick to Rapid Spin/Defog support, or use Espeon or Mega Absol.

In the end, here's what a possible team for you should look like:

* Charizard X (see above set)

* Rapid Spin/Defog user (see above)

* Greninja

* Ferrothorn or Skarmory (provides hazards):

Ferrothorn:
-Stealth Rock/Spikes
-Leech Seed
-Power Whip/Protect
-Gyro Ball/Thunder Wave
Nature: Relaxed
EVs: 252 HP/48 Def/208 SDef
Item: Leftovers/Shed Shell/Rocky Helmet
Ability: Iron Barbs

Skarmory:
-Roost
-Whirlwind
-Stealth Rock/Spikes/Brave Bird
-Defog/Brave Bird
Nature: Bold/Impish
EVs: 252 HP/252 Def/4 SDef or 252 HP/16 Def/240 SDef
Item: Leftovers/Rocky Helmet
Ability: Sturdy

or
-Spikes
-Roost
-Whirlwind
-Taunt/Brave Bird
Nature: Bold/Impish
EVs: 252 HP/184 Def/72 Spe
Item: Leftovers
Ability: Sturdy

Therian Landorus or Scizor (to form a U-turn core with Greninja):

Therian Landorus:
-Stealth Rock
-Earthquake
-U-turn
-Stone Edge/Knock Off/Hidden Power (Ice)
Nature: Adamant/Naughty
EVs: 248 HP/16 Atk/244 Def
Item: Leftovers

or
-Earthquake
-Stone Edge
-U-turn
-Knock Off/Superpower/Hidden Power (Ice)
Nature: Jolly/Naive
EVs: 252 Atk/4 Def/252 Spe
Item: Choice Scarf

Scizor:
-U-turn
-Bullet Punch
-Superpower/Brick Break
-Pursuit/Knock Off
Nature: Adamant
EVs: 248 HP/252 Atk/8 SDef
Item: Choice Band
Ability: Technician

or
-Swords Dance
-Bullet Punch
-U-turn/Bug Bite
-Roost
Nature: Adamant
EVs: 248 HP/44 Atk/216 SDef
Item: Leftovers
Ability: Technician

* Dragonite (see above set)