Battle Moveset

A Good Moveset for Flygon would have to be this:

Attacks:

Earthquake
Rock Slide
Fire Blast / Flamethrower
Hidden Power [Bug]

Items Attached:

Leftovers OR
Choice Band

Preferred Nature:

Adamant.

Strategy Using Flygon

This is the most common variation of Flygon. With Rock Slide and Earthquake it can get a solid hit in on most Pokémon. With Hidden Power [Bug] it can get at super-effective hit on most of the Pokémon who can handle EQ-Rock Slide with ease (Celebi and Claydol are the main ones) and with Fire Blast or Flamethrower it has a strong move to hit Skarmory or Forretress with.

? One of the main draws of using Flygon is it's many resistances to common attacks, Rock and Ground attacks first and foremost (messing up many common sweepers), so the hit and run style of Choice Band fits it well: switch in, attack and switch out. While most people choose to run Flygon with Choice Band, giving it a much stronger punch, some however will opt for Leftovers, sacrificing power in favour of versatility.

EV Corner:

EVs: 252 Atk / 252 Spd / 4 SAtk
Adamant Nature (+Atk, -SAtk)

Even though you'll have Fire Blast it's best not to lower Flygon's defensive stats, especially since it's Fire Attacks will only be used for two Pokémon (Skarmory and Forretress). Fire Blast can 2KO Skarmory with it's base Special Attack but you'll need a little more for Flamethrower to 2KO it (in this case you probably will opt for a Naughty nature to achieve a high enough stat without too much EV waste). Some people opt for lower speed stats, 270 being the main one to guarantee that it'll outrun Adamant Heracross and other Pokémon who linger in that range. If you opt for Max Speed make sure when setting a Hidden Power that the IV is 31 however.

Other Optional Sets

Flygon @ Leftovers
Trait: Levitate
EVs: 4 Atk / 252 Spd / 252 SAtk
Rash Nature (+SAtk, -SDef)
- Flamethrower / Fire Blast
- Dragon Claw
- Earthquake
- Hidden Power [Ice] / Giga Drain / Crunch

This is the rarely used Special variation of Flygon. It's average Special Attack doesn't lend too well to Special offence but it's wide move pool gives it some support, as well as having a Special STAB that's only resisted by one type (Steel, which gets hard by Fire attacks anyway). It's a bit of a novelty but it's one of those surprise sets that isn't doomed to failure. Using Flamethrower/Fire Blast as well as EQ will also leave your opponent expecting the physical variation of Flygon anyway so you can prolong the element of surprise for a little while. The final move is up to choice, HP Ice does a fair bit more to Dragons than Dragon Claw, Giga Drain can hit Swampert hard as well as hitting other Waters for super effective, recovering a little health is a nice bonus of it and Crunch hits super-effective to a handful of common Pokémon (Celebi, Gengar and the Psychic gang).

Other Optional Moves

Screech, Substitute, Quick Attack, Hidden Power [Flying], Hidden Power [Ghost], Solarbeam. Screech and Sub are the most effective here, commonly used on the first set in it's Leftovers variation. Screech will probably force anything to switch out in fear of taking a massive Earthquake (or Rock Slide) and with Spikes support scores some bonus damage. Substitute blocks the next attack, making things a bit tougher on the next switch in as well as giving you some prediction leeway. Quick Attack is obvious, Choice Band + High Attack + Priority always has it's uses. Since Heracross frequently switches into Flygon to block it's Earthquake/HP Bug/Rock Slide a quick HP Flying can take it out of the battle, as a bonus HP Flying still hits Grass types for super effective like HP Bug. HP Ghost can take out Gengar, as a bonus it also still hits Celebi decently. I suppose Solarbeam is worth a mention if you ever considered using Special Flygon in ubers, that's pretty much the full extent of what it can do with Solarbeam. With Flygon's natural defence it can take a Sword Dance boosted Rock Slide from Groudon whilst only losing about a third of it's HP, isn't too shabby…although it still probably isn't a wise idea to send Flygon into ubers anyway.

Strategy Against Flygon

Since Flygon frequently carries Choice Band prediction is the first key. Regardless of the type of Flygon Earthquake is essentially guaranteed to be on it's set so don't go throwing anything weak to Earthquake out into play unless you're doing. For the most part the 'bulky waters' are considered the best general counters to Flygon, even the special variation of Flygon has no moves that are particularly threatening to a Water type (barring Giga Drain to Swampert), even with Hidden Power it's Special Attack won't be able to do much. Provided Heracross doesn't switch straight into a Fire Blast it can fair well against Flygon, it resists EQ and HP Bug and takes normal damage from Rock Slide (which is a weak move without the super-effective boost), it's defence can't handle taking too many hits though. Provided you don't become exposed to a Fire attack Skarmory handles Flygon with ease. When HP Bug is absent Claydol tramples over Flygon (and even if HP Bug is there, if you don't switch into it Flygon will need to run from Ice Beam), similar story for Celebi although Celebi may still have problems with a potential HP Flying. Anything faster with an Ice Attack wins by default if it gets into play against it. Fellow Flygon's manage the physical sets easily, however without a different variation it's pretty much a stalemate since both Flygon's resist each other (of course if you switched into a Flygon using EQ you could sit there hitting a lot of HP Bug's until it switched).

Contest Moveset

A good Contest Moveset for Flygon would have to be this for the Beauty Contest best with Modest, Mild, Rash or Quiet Nature:

Attacks:

Sunny Day
Aerial Ace
Flamethrower
Hyper Beam

Items Attached:

Blue Scarf

Strategy Using Salamence

If you do the attacks in this following order you should have very few problems; 1st - Aerial ace, 2nd - Sunny day, 3rd - Flamethrower, 4th - Aerial ace, 5th - Hyper beam

Locations in Games

Ruby/Sapphire/Emerald Evolve Vibrava Colosseum & XD Evolve Vibrava Fire Red/Leaf Green Trade from RSECXD

Animé Appearences

Flygon has had several Animé Appearences. First one was used to help Ash & Co. protect Jirachi from a Groudon Monster. After that, Drew used one in many of his contests and appearances. The rest are cameos. Episode 336: Delcatty Got Your Tongue Movie 6: Jirachi - Wish Maker Episode 400: Rhapsody In Drew Episode 416: On Cloud Arcanine Episode 451: May VS Jessie! The Final Contest Episode 457: May VS Harley! Double Battle On Stage Episode 458: May VS Drew! The Final Battle