Pokemon Name: Flygon
Moveset Name: Sleep Talker
Move 1: Rest
Move 2: Sleep Talk
Move 3: Outrage / Stone Edge
Move 4: Earthquake / U-Turn
Item: Leftovers / Life Orb
Ability: Levitate
Nature(s): Jolly (+Spe, -SpA)
EVs: 252 HP / 160 Def / 16 SpD / 80 Spe
Description: This set is intended to take advantage of Flygon's excellent typing and ability, granting it many resistances and two immunities. Flygon is capable of dishing out offense, but many times you will find yourself trapped in Outrage too early, or maybe you just hate when that Heat Wave or Fire Blast, from Zapdos or Heatran, respectively, burns you. This set tries to remedy that while giving Flygon the ability to revenge kill/check several threats in the current metagame.
Moves: Rest + Sleep Talk are obvious, as the title is referring to them. Rest allows Flygon to rid itself of annoying statuses, such as burn and poison, as well as bringing its HP to 100%. Sleep Talk prevents Flygon from becoming setup fodder while it is asleep, and allows it to absorb sleep too.
As far as the other moves are concerned, there are plenty of options, but his STAB moves are recommended. I designed this set around Outrages flaws, and is really Flygon's best option when paired with Rest + Sleep Talk. STAB Earthquake is there for "checking" modern threats, most of which take atleast neutral from ground, although if that is the case then I sugget using some other pokemon, as this Flygon's advantage is using its Subpar attack score to kill some vital pokemon with super effective hits. However, if you opt for other coverage, then Stone Edge is your best bet. It retains coverage on Salamence, and it hurts Gyarados + Zapdos too. It pairs well with EQ, as Ground + Rock provides solid coverage. Another option is U-Turn > Earthquake. This allows you to scout which Hidden Power the opponent's Zapdos has, thus allowing you to send in your Swampert or other ground which is not 4x weak to ice. So here are the most efficient combinations:
I have tested all of these, and the order they are in is how effective I found them to be.
Outrage + Earthquake-This is by far the most effective combination. He isn't using attack EVs so STAB is really needed, and STAB Outrage has 180 power, which isn't much less than a super effective Stone Edge. It also abused the Sleep Talk theme, and with Earthquake I could revenge kill Lucario and Heatran.
Stone Edge + Earthquake-
This worked decently, until I realized that Stone Edge was doing shit to Gyarados, and it was better to send in my bulky water, which I already had for certain Heatrans.
Outrage + U-Turn-
U-Turn did fairly well against Zapdos, especially since I had a CursePert waiting, but the lack of STAB Earthquake really hurt the set, as I couldn't take down Lucario or Tyranitar, and I would have to stall against Heatran.
Other moves I have tested include Fire Blast and Fire Punch, neither of which were doing any significant damage to the pokemon Flygon can switch into.
A few threats that this Flygon is capable of "checking" that the Choice Bander or Roosting sets cannot handle include: Toxi/Sub Heatran, Rhyperior, Lucario, Gengar, Rotom-A, Tyranitar, SubRoost Zapdos, ToxiStall Vaporeon, etc. The main objective of this set is to use Rest as a recovery mechanism, but it can also absorb sleep from the main users with little risk:
359 Atk Breloom's Superpower vs. 364 HP/236 Def Flygon:54.39%-64.01%
359 SpA Gengar's Shadow Ball vs. 364 HP/200 SpD Flygon:42.85%-50.27%
These are the most offensive sleepers in OU, and Breloom's calculation is assuming Choice Scarf with a Jolly nature, because if he has an Adamant nature he likely isn't using Superpower, and Focus Punch will be disrupted roughly 66.67% of the time by EQ or Outrage. So even if you don't predict correctly, neither one of these pokemon are likely going to 2HKO you (Breloom has a slight chance), so absorbing sleep should be easy enough. Let's take a look at how much this takes from common threats:
All assuming 364 HP / 236 Def / 200 SpD:
400 Atk Rhyperior's Stone Edge: 25.27%-29.67%
4-5HKO
400 Atk +2 Rhyperior's Stone Edge: 50.27%-59.06%
2-3HKO
403 Atk CB Tyranitar's Crunch: 60.98%-71.42%
2HKO-Need to revenge
350 Atk +2 LO Lucario's Extremespeed: 60.98%-71.70%
Switch into SD
359 SpA Heatran's Fire Blast: 31.86%-37.63%
3-4HKO
Although these may seem miniscule, switching into resisted and neutral hits are what this Flygon is meant for, as there is no possible way Flygon can act as a pure wall, or even a tank for that matter. This set is just a great check for these pokemon and it isn't bothered by status, so you can pack one of these alongside your bulky water to beat any Heatran you come by. Now for some offensive calculations against the aforementioned threats:
All assuming 236 Atk:
vs. 434 HP/296 Def Rhyperior: 32.67%-38.11%
3-4HKO
vs. 404 HP/256 Def Tyranitar: 50%-58.91%
2HKO
vs. 281 HP/177 Def Lucario: 100%
Easy OHKO
vs. 324 HP/248 Def Heatran: 100%
Easy OHKO
You can opt for Life Orb to 3HKO SubPerior(Rhyperior) every time, although it isn't recommended as this Flygon's job is just to stop slower sweepers/choicers who are weak to EQ, and adding LO "recoil" will somewhat reduce its effectiveness.
EVs: The speed allows you to outrun Max speed Adamant Lucario, as well as many of the pokemon who try and outrun Luke. Max HP allows it to switch into Fire Blasts, Heat Waves, and Stone Edges a lot easier. The defense ensures you will never be 2HKOed by CB Tyranitar's Stone Edge, provided you are using Leftovers, and it also guarantees survival against a CB Tyranitar's Crunch, so if you need to revenge kill him, this can do it for you. The special defense brings it to 200, making this a better counter for electric types without Hidden Power Ice than Steelix.
You can go a different route with this set, using Earth Power + Dragon Pulse/Flamethrower over the current set. Just switch to a Timid nature. However, I strongly recommend not doing so, as Earthquake does more to Tentacruel, Heatran, Tyranitar, and Earth Power doesn't score any significant 2-3HKOs on things like Rhyperior, since SubPerior, the set I have been doing calcs for, is not used without Sandstream. It does help Flygon "check" Scizor, but you are better off just using a Magnezone so you can trap Skarmory, who loves switching into this set.