Time to review your team.
Garchomp: you should really
add some coverage to
Fairy and
Ice-types since you have so many
stabs moves it's just best limit to
2 or
1 stab moves and both
Dragon Rush and
Dragon Claware decent moves I always go with
Dragon Claw on this one since it's good base power and accuracy, Dragon Rush sometimes miss and you might go use
Earthquake
Moves recommend:
- Iron Head (good against ice and fairy)
- Earthquake (if you don't plan to triple/double battle)
- Choose either Dragon Claw/Dragon Rush
Charizard X: Fire blast only good with
Charizard Y since utilizing
drought ability pretty well, you should maybe teach it
dragon claw since it add bit of boost due to
tough claws again just so much or bit little coverage.
Gengar: I think your good here, but did you know gengar could learn
Dazzling Gleam it good with it's special attack stats
Greninja: You can't
sub from
Pixilated Hyper Voice and you may need bit of coverage against
Grass & Fighting also Hydro is raw power, but misses a lot.
A 2x supereffective Iron Head barely outdamages a neutral STAB Earthquake. It's not that useful on Garchomp. Calcs to prove it:
252 Atk Garchomp Earthquake vs. 0 HP / 4 Def Mega Altaria: 151-178 (51.8 - 61.1%) -- guaranteed 2HKO
252 Atk Garchomp Iron Head vs. 0 HP / 4 Def Mega Altaria: 160-190 (54.9 - 65.2%) -- guaranteed 2HKO
Dragon Rush is also a bad attack on Garchomp because of its poor accuracy. Outrage is the superior strong Dragon STAB, since it's also 100% accurate.
Anyway, what format is this team for? Battle Spot? Standard Smogon OU? If it's the latter, you can't use Greninja and Aegislash because they're Uber Pokemon. In Battle Spot, you're free to use either of them. Also include the EVs of each Pokemon as they're very important in competitive battling. You may have to do some re-breeding on your Pokemon, as their natures are bad.
Battle Spot:
Snorlax isn't a good Pokemon to use there and in Smogon OU. It's way too slow to utilize Belly Drum effectively. You can get away with using 2 Mega Evolutions in Battle Spot, so replace Snorlax with either Mega Kangaskhan or Mega Lopunny, as they're both stronger and faster than Snorlax:
Kangaskhan:
-Return/Double-Edge
-Power-Up Punch
-Sucker Punch
-Earthquake/Rock Slide/Substitute/Secret Power
Nature: Jolly/Adamant
EVs: 252 Atk/4 SDef/252 Spe
Item: Kangaskhanite
Ability: Scrappy
or
-Return/Double-Edge
-Earthquake
-Sucker Punch/Fake Out
-Rock Slide/Ice Punch/Fake Out/Facade
Nature: Jolly/Adamant
EVs: 252 Atk/4 SDef/252 Spe
Item: Kangaskhanite
Ability: Scrappy
Lopunny:
-Fake Out
-Return
-High Jump Kick
-Ice Punch/Baton Pass/Substitute
Nature: Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Lopunnite
Ability: Limber
A Sassy nature wastes away Charizard X's decent Speed. It relies on said Speed to accomplish its sweeping job. As Undyne already mentioned, Charizard X is better with physical moves, due to Tough Claws. Fire/Dragon also has reasonably good offensive coverage; why aren't you taking advantage of this? Solar Beam requires a charge-up turn outside of sunlight and it's not that useful on Charizard X, since it's neutral to Water moves and can also use Earthquake to hit Rock Pokemon. Steel Wing is useless outside of hitting Mega Diancie, which is already chunked by Earthquake or Tough Claws Flare Blitz anyway:
-Dragon Dance
-Flare Blitz
-Dragon Claw
-Roost/Earthquake
Nature: Jolly/Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Charizardite X
Ability: Blaze
or
-Flare Blitz
-Dragon Claw/Earthquake
-Will-o-Wisp
-Roost
Nature: Impish
EVs: 248 HP/100 Def/160 Spe
Item: Charizardite X
Ability: Blaze
or
-Swords Dance
-Flare Blitz
-Outrage/Dragon Claw
-Tailwind/Roost
Nature: Adamant
EVs: 40 HP/252 Atk/216 Spe
Item: Charizardite X
Ability: Blaze
Charizard Y is still an option when you really want to use special moves on Charizard. Note that Charizard Y has Drought to make Solar Beam a 1-turn attack:
-Fire Blast/Flamethrower
-Solar Beam
-Focus Blast
-Roost
Nature: Timid/Modest
EVs: 252 SAtk/4 SDef/252 Spe
Item: Charizardite Y
Yes, Garchomp can go the bulky route, but it really appreciates the raw power of Earthquake. Sand Tomb is a very weak attack and its trapping ability isn't a reason to be using it, as Levitate and Flying Pokemon are immune to it:
-Outrage
-Earthquake
-Stealth Rock/Swords Dance
-Rock Tomb/Dragon Claw/Fire Blast
Nature: Jolly/Naive
EVs: 4 HP/252 Atk/252 Spe
Item: Focus Sash/Lum Berry/Rocky Helmet
Ability: Rough Skin
or
-Outrage
-Earthquake
-Dragon Claw/Dual Chop
-Rock Slide/Stone Edge/Fire Fang/Fire Blast
Nature: Jolly/Naive
EVs: 4 HP/252 Atk/252 SPe
Item: Choice Band/Choice Scarf
or
-Swords Dance
-Outrage
-Earthquake
-Dragon Claw/Dual Chop/Stone Edge/Draco Meteor/Fire Blast
Nature: Jolly/Naive
EVs: 4 HP/252 Atk/252 Spe
Item: Life Orb
Brick Break is a useless move on Gengar, as it works off of its inferior Attack stat. Focus Blast is the better option, despite its accuracy. Remember that Ghost hits Steel neutrally this generation, so Gengar can get away without a Fighting move in some cases. Anyway, here are better sets for it here:
-Shadow Ball
-Sludge Bomb
-Focus Blast
-Destiny Bond/Icy Wind
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb/Focus Sash
or
-Substitute
-Disable
-Shadow Ball
-Focus Blast
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Black Sludge
As with Charizard, Greninja relies on its Speed to be effective and Gentle doesn't help that stat, or any other stat required on an offensive Pokemon in general. Greninja has a wide move pool and you're not taking advantage of that in conjunction with its Protean ability. It's also too frail to rely on supporting/disrupting moves like Haze and Substitute. The only use for Water Shuriken is to revenge kill Talonflame and (Mega) Blaziken. Other than that, it's not very useful, as Greninja is already very fast:
-Ice Beam
-Dark Pulse
-Gunk Shot
-Hydro Pump/Water Shuriken/Low Kick/Grass Knot
Nature: Naive
EVs: 20 Atk/236 SAtk/252 Spe
Item: Life Orb
Ability: Protean
Aegislash can effectively make use of Stance Change to tank hits in Shield Forme, then attack in Blade Forme. It can revert to Shield Forme with King's Shield to protect itself from offensive attacks:
-Shadow Ball
-Flash Cannon/Sacred Sword
-Shadow Sneak
-King's Shield
Nature: Quiet
EVs: 252 HP/252 SAtk/4 SDef
Item: Leftovers/Weakness Policy
or
-Substitute
-Toxic
-King's Shield
-Shadow Ball/Flash Cannon
Nature: Modest/Timid
EVs: 252 HP/252 SAtk/4 Spe or 252 HP/4 SAtk/252 Spe
Item: Leftovers
or
-Iron Head/Shadow Claw
-Shadow Sneak
-Sacred Sword
-King's Shield/Swords Dance
Nature: Adamant/Brave
EVs: 252 HP/252 Atk/4 SDef
Item: Life Orb/Leftovers/Weakness Policy
Smogon OU:
As Mega Kangaskhan is an Uber and your Mega slot is taken up by Charizard, I'd suggest a Rapid Spin or Defog user here, as Charizard is weak to Stealth Rock. An example is Starmie:
-Hydro Pump
-Psychic/Psyshock/Thunderbolt
-Ice Beam/Hidden Power (Fire)
-Rapid Spin
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb
Ability: Natural Cure/Analytic
or
-Scald
-Reflect Type/Psyshock
-Rapid Spin
-Recover
Nature: Timid
EVs: 252 HP/4 SAtk/252 Spe
Item: Leftovers
Ability: Natural Cure
Refer to the Battle Spot section for viable Charizard sets.
Garchomp can act as the Stealth Rock setter of the team. Stealth Rock is a very important entry hazard in competitive play, as it helps achieve KOs you normally wouldn't get without it and
it does damage based on the switch-in's type. Don't use Sand Tomb on the defensive set, as even though this Garchomp defensive, it focuses more on chipping away on physical attackers with Rough Skin + Rocky Helmet:
-Stealth Rock
-Outrage/Dragon Claw
-Earthquake
-Fire Blast/Swords Dance
Nature: Naive/Jolly
EVs: 252 Atk/4 SAtk/252 Spe
Item: Life Orb/Lum Berry/Focus Sash
or
-Stealth Rock
-Dragon Tail
-Earthquake/Toxic
-Fire Blast/Toxic
Nature: Impish
EVs: 240 HP/176 Def/92 Spe
Item: Rocky Helmet
Ability: Rough Skin
Like before, Brick Break isn't a useful attack on Gengar. It can run different sets in standard OU, even a utility set:
-Shadow Ball
-Sludge Bomb/Sludge Wave
-Focus Blast
-Destiny Bond/Taunt/Icy Wind/Substitute
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb/Focus Sash/Black Sludge
or
-Hex
-Taunt
-Will-o-Wisp
-Sludge Bomb/Sludge Wave/Substitute
Nature: Timid
EVs: 8 HP/248 SAtk/252 Spe
Item: Black Sludge
Greninja and Aegislash are banned to Ubers as previously mentioned. Replacements to both are Weavile or Azumarill for Greninja and Bisharp or Skarmory for Aegislash:
Weavile:
-Knock Off
-Icicle Crash
-Ice Shard
-Low Kick/Poison Jab/Pursuit
Nature: Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Life Orb
Ability: Pressure
Azumarill:
-Waterfall
-Play Rough
-Aqua Jet
-Knock Off/Superpower
Nature: Adamant
EVs: 164 HP/252 Atk/92 Spe (Choice Band) or 240 HP/252 Atk/16 SDef (Assault Vest)
Item: Choice Band/Assault Vest
Ability: Huge Power
or
-Belly Drum
-Aqua Jet
-Play Rough
-Knock Off
Nature: Adamant
EVs: 92 HP/252 Atk/164 Spe
Item: Sitrus Berry
Ability: Huge Power
Bisharp:
-Sucker Punch
-Iron Head
-Knock Off
-Pursuit/Swords Dance
Nature: Adamant/Jolly
EVs: 4 HP/252 Atk/252 Spe or 204 Atk/52 SDef/252 Spe
Item: Black Glasses/Dread Plate/Life Orb/Lum Berry
Ability: Defiant
or
-Sucker Punch
-Iron Head
-Knock Off
-Pursuit
Nature: Adamant
EVs: 192 HP/220 Atk/96 Spe
Item: Assault Vest
Ability: Defiant
Skarmory:
-Spikes
-Brave Bird/Iron Head
-Whirlwind/Taunt
-Roost
Nature: Impish/Careful
EVs: 252 HP/252 Def/4 SDef (Impish) or 252 HP/4 Def/252 SDef (Careful)
Item: Rocky Helmet/Leftovers
Ability: Sturdy
