XY OU Help on my team!

[ネ久サス]

Hey guys,
I'm starting to play the Pokemon metagame, it would be awesome if you can help me build my team since I don't know much yet.
This team is based on my friend's team that already got some help from here. The only requirements I have is to keep my Charizard (I'd like to have a X instead of the Y below since that's the version of my game) and introduce a Gengar. How could I do that? All the other Pokemons can be swapped for anything you feel it's better for me.

The other Pokemons that I wouldn't mind having in my team are:
Rotom-w
Scizor
Venusaur
Vaporeon
Mawile
Keldeo
Dragonite
Clefable
Azumarill

Tyranitar @ Smooth Rock
Ability: Sand Stream
EVs: 248 HP / 252 Def / 8 SpD
Impish Nature
- Stealth Rock
- Stone Edge
- Pursuit
- Ice Beam

Greninja @ Life Orb
Ability: Protean
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk / 30 SpA / 30 Spe
- Hidden Power [Fire]
- Hydro Pump
- Ice Beam
- Extrasensory

Charizard @ Charizardite Y
Ability: Blaze
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Fire Blast
- Solar Beam
- Focus Blast
- Dragon Pulse

Zapdos @ Leftovers
Ability: Pressure
EVs: 252 HP / 252 SpD / 4 Spe
Calm Nature
IVs: 0 Atk
- Thunderbolt
- Roost
- Toxic
- Heat Wave

Excadrill @ Life Orb
Ability: Sand Rush
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Earthquake
- Rock Slide
- Iron Head
- Rapid Spin

Garchomp @ Choice Scarf
Ability: Rough Skin
EVs: 252 Atk / 4 SpD / 252 Spe
Naive Nature
- Outrage
- Earthquake
- Rock Slide
- Dragon Claw

As I said before, I'm pretty new in this metagame so I'd appreciate any suggestions you have for me.

 

[mcp3]

Add HP ice on Zapdos to catch Lando on the switch. I would also add AV azumarill because Keldeo and opposing greninja are big threats to this team. Char Y also could use roost instead of dragon pulse; if you would like to hit the Lati twins just trap them with your tyranitar. Change Garchomp to a sash lead with stealth rock, and make tyranitar your scarf because mew and mega pinsir are huge threats to your team too.

Azumaril @ Assault Vest
Nature: Adamant
Ability: Huge Power
Evs: 240 HP 252 Attack 16 Speed
- Waterfall/Superpower
- Knock off
- Aqua jet
- Play rough

Tyranitar @ Choice Scarf
Nature: Jolly
Ability: Sand Stream
Evs: 252/252 Attack Speed 4 Def
- Superpower
- Pursuit/Crunch
- Stone edge/Rock slide
- Ice beam/Fireblast

Garchomp @ Focus Sash/ Life orb
Nature: Naive
Ability: Rough Skin
Evs: 252/252 Speed Special attack 4 Def
- Draco metor
- Fire blast
- Earthquake
- Stealth Rock

 

[Noir bear]

The team gets shitted on by scarfed terrakion once your squad is weakend down mid-game