Thanks for checking. The spacing errors are the result of when I copy/pasted a draft from Word.GP check on request
Once In the earlier years of VGC, Hydreigon was considered nearly uncounterable,(comma) in the earlier years of VGC, Hydreigon yet it now has a difficult time holding that title maintaining this status. Hydreigon gained Gaining a 4x weakness with the introduction of Fairy-types, and consequently, it Hydreigon now has a harder time staying alive, and its base 98 Speed, which falls short of the 100 base Speed tier, is now even more problematic than it was in the last generation speed doesn'tdo it any favors either. Its Dark typing also brings extra Fighting- and Bug-type weaknesses to the table.(full stop) ,(remove) which lessens its longevity. On top of all this, it's not the only dragon available; Hydreigon also faces stiff competition with from faster and more bulkier dragons,(comma) including old rivals such as Salamence,(remove) and Garchomp, and even as well as newer dragons such as Noivern and Goodra.
However, don't count Hydreigon out just yet. Boasting a Thanks to its base 125 Special Attack stat, Hydreigon is the strongest specially-based dragon in the metagame. Hydreigon is also able to hit Steel types with its STAB moves, as Dark-type moves are no longer resisted by Steel-types, with its buffed Dark typing, giving it great coverage with its STABs alongside its Dragon-type attacks. Its typing and Levitate ability also give it immunities to both Ground- and Psychic-type moves,(comma) which combined with its .(remove) Hydreigon also has above average 92/90/90 bulk and slew of resistances means it can take an attack or two along the way allowing it to take moderately powerful attacks. Finally, Hydreigon is quite versatile and has a vast movepool, allowing it to run a physical or even mixed set to surprise its opponent if need be. Even though it's slower then than its dragon brethren, Hydreigon's raw power will not disappoint.
[A bunch of stuff from your skeleton was completely left out. Was this intentional? This overview seems somewhat bare-bones as it is]
name: Special Hydra
move 1: Draco Meteor / Dragon Pulse
move 2: Dark Pulse
move 3: Fire Blast / Flamethrower
move 4: Protect
item: Life Orb / Focus Sash
evs: 4 HP / 252 SpA / 252 Spe
nature: Timid / Modest
[are you allowed to make up set names like this? Wouldn't "Special Attacker" be more appropriate?]
This set abuses uses Hydreigon's strengths to their fullest, particularly with regard to and its unparalleled power. Draco Meteor is Hydreigon's main STAB move and does a hefty amount of damage to the majority of the metagame. Alternatively, Dragon Pulse can also be used over Draco Meteor if the Special Attack drop is unappealing, though the lack of decrease in power is noticeable. Dark Pulse is Hydreigon's second STAB attack, giving and gives it good coverage on against the majority of the tier;(semicolon) between its two STAB moves, Hydreigon only hits bar Fairy-types and select Pokemon like Bisharp for anything less than neutral damage.(full stop) Dark Pulse also allows Hydreigon to hit ,(remove) while hitting Psychic- and Ghost-types such as Chandelure and Aegislash for super effective damage [why did you leave out the bit about OHKOs and 2HKOs?]. Fire Blast hits Steel-types for super effective damage and is Hydreigon's best way of getting past them,(comma) Steel-types,(remove) hitting them for super-effective damage. as while Flamethrower is a more accurate option,(comma) over Fire Blast, but it has less power and will not net a an OHKO on Ferrothorn without a Modest nature. Protect is a useful utility move that allows Hydreigon to avoid getting double targeted and to potentially give your teammate free turns [I surmise that what you're trying to say is that if Hdgon is double-targeted then this means that your other Pokemon gets a free turn, but this in no way is due to Protect so this statement is misleading; feel free to explain what you mean in more detail if you wish but the statement is far too nebulous as is].
Full investment in Speed and Special Attack along with a Timid nature allows it makes Hydreigon to be as fast as possible, attempting hopefully negating the impact of its to overcome its awkward speed Speed tier,(comma) while Special Attack is also maximized for obvious reasons while also maximizing power. If you are not concerned about speed Speed, Hydreigon can run a Modest nature instead to increase the power of its attacks even further. Life Orb is its main recommended for the item in order to give Hydreigon an extra power boost, but,(remove) if you're worried about Hydreigon going down too quickly, Focus Sash is another option.
Even though Hydreigon's power is unrivaled, it still needs to play conservatively to overcome its weaknesses to Fighting-, Bug-, and Fairy-types; especially as Fairy-types can switch in for free on its Dragon-type attacks. the latter of which Hydreigon has a 4x weakness to. If Fairy-types aren't on the field, then Hydreigon can be played more aggressively to attempt to obtain early OHKOs.
Steel-types such as Ferrothorn and Aegislash in particular are tremendously helpful in dealing with Fairy-types. The former is able to stall out threats such as Mawile with the combination of Leech Seed and Protect, and the latter is immune or resistant to all of Hydreigon's other weaknesses. However, Aegislash must be careful in order to play around Mawile's Sucker Punch. Amoongus Amoonguss pairs well with Hydreigon, providing thanks to its access to Rage Powder,(comma) support to redirect moves aimed at it Hydreigon towards itself, and Spore,(comma) to temporarily incapacitate the opponent's Pokemon.(full stop) This means that it can provide Hydreigon with the free turns it needs ,(remove) giving Hydreigon a free turn in which to deal heavy damage. Any Rotom form forme, especially Rotom-Heat, can provide Thunder Wave support to help Hydreigon overcome its awkward speed Speed tier,and can also provide dual screens screen support to help Hydreigon tank take hits more easily.
name: Scarf Hydra
move 1: Draco Meteor
move 2: Dark Pulse
move 3: Fire Blast / Flamethrower
move 4: U-turn / Dragon Pulse
item: Choice Scarf
evs: 4 HP / 252 SpA / 252 Spe
nature: Modest / Timid
Equipping a Choice Scarf allows Hydreigon to overcome bypass the ill effects of its base 98 speed Speed tier,(comma) thus allowing it to outspeed threats it otherwise wouldn't be able to. Draco Meteor is Hydreigon's strongest STAB move and even without a boosting item hits exceptionally hard off a with its invested base 125 Special Attack stat ,(remove) will hit hard. Dark Pulse is Hydreigon's safest secondary, reliable STAB attack, and can be used where Draco Meteor would be unnecessary as it has no noticeable drawbacks such as stat drops or low accuracy. Fire Blast is Hydreigon's main way of getting through Steel-types such as Mega Mawile. Flamethrower can be used over Fire Blast, but without a boosting item, it will not do significant damage to its intended targets. U-turn is used to switch out of bad situations while chipping away at the opposing Pokemon's health. However, If you are wholly averse to Draco Meteor, then Dragon Pulse can be used along with Dark Pulse, which makes Hydreigon better at cleaning can be used to clean up weakened teams.
The EV spread with a Modest nature emphasizes power instead of speed Speed,(comma) because thanks to the Choice Scarf, Hydreigon will not be outspeeding much with a speed-boosting nature that it couldn't without. If you are worried about speed Speed tying with other Scarfed Hydreigons opposing Choice Scarf Hydreigon, a Timid nature is a perfectly reasonable choice instead.
Hydreigon needs to be played carefully around Fairy-types,(comma) as it could possibly be locked into a Dragon-type move on a Fairy-type. Hydreigon should ideally be used as a pseudo-revenge killer to pick off weakened foes. If the situation is unfavorable, Hydreigon should U-turn out and switch into an appropriate counter to deal with the threat. Also, you should abuse make use of Hydreigon's immunity to Ground-type attacks to safely switch into predicted Earthquakes to deal damage. Finally, before using Choice Scarf Hydreigon aggressively, you should pick off faster Choice Scarf users that can knock out Hydreigon before it can even react move.
As Fairy-types are especially problematic, a Steel- or Poison-type partner can should be used in order to deal with them. Bisharp is especially helpful as it can easily deal with the majority of Fairy types in the meta metagame while also providing Knock Off support to remove Choice Scarves Choice Scarf from faster opposing Pokemon. With the Speed increase granted by Choice Scarf, Hydreigon can function as a scout with U-turn. Because of this, Intimidate users such as Mawile,(remove) are quite handy in order to weaken physical attackers on the switch-in. Gardevoir can aid Hydreigon by picking off faster Scarfed Choice Scarf Dragon-types such as the common Choice Scarf Salamence.
Hydreigon has a versatile movepool and can run a variety of moves to surprise its opponent. For example, Hydreigon can run a mixed set with Stone Edge or Rock Slide to hit Charizard-Y and Talonflame, the former OHKOing and the latter 2HKOing the two. It can also run a physical set with moves such as Acrobatics, Earthquake, and Crunch,(comma) but Hydreigon will unfortunately have to rely on the inaccurate Dragon Rush or the unpredictable Outrage for a Dragon-type STAB attack. Hydreigon also has a vast special movepool that it can work with, including attacks such as Earth Power, Focus Blast, and even Surf. Hydreigon can also run Flash Cannon to try to hit Fairy-types, but generally it won't do enough damage to be significant [calcs?]. In addition to having a movepool as vast as the ocean, Hydreigon can also run a variety of items and EV spreads to perform a specific niche. The most notable is running Choice Specs to provide even more power for Hydreigon. It can also run Safety Goggles or Lum Berry to counter Charizard-Y and Venusaur teams by being immune to Sleep Powder. A Haban Berry with a spread of 236 SpA / 132 SpD / 140 Spe with a Modest nature can be used to tank a Timid Specs Salamence's Draco Meteor so that Hydreigon can retaliate with its own Draco Meteor while still outspeeding invested base 70s. Lastly, a bulkier spread of 68 Def / 224 SpA / 216 Spe with a Timid nature can be used to survive Jolly Garchomp's Dragon Claw while still allowing Hydreigon outspeed invested base 92s.
Checks & Counters
While it may seem like Hydreigon is unpredictable, it does have some hard counters that can easily force it out. The most obvious counters are Fairy-types,(comma) as Hydreigon really cannot do anything against them. Azumarill in particular resists both of Hydreigon's STABs STAB moves as well as Fire Blast and most of its other coverage moves, and only fears fearing the rare Hidden Power Powers. Faster Dragon-types such as Salamence can OHKO Hydreigon before it can do anything. Assault Vest Conkeldurr can easily tank a Draco Meteor and OHKO Hydreigon while healing back up with Drain Punch. Specially Defensive Tyranitar can take any move Hydreigon has in store bar a Life Orb Focus Blast and retaliate back with a Brick Break. Another threat that can destroy Hydreigon is Mega Lucario, as both physical and special variants can 2HKO with Mach Punch and Vacuum Wave respectively, though it should be wary of Fire Blast. Mamoswine can also 2HKO with Ice Shard and can potentially OHKO with Icicle Crash, and like Tyranitar it only fears the rare while only fearing the rare Focus Blast.
[I thought this was meant to look like a threatlist but meh I prefer paragraphs]
This turned into something of a christmas tree; there are quite a few simple errors, repeated phrases, and wonky prose choices. More to the point, it seems like a lot of information from the skeleton never appeared in the final write-up, I don't recall set names allowing nicknames before, and there are other assorted complaints in the text. I feel like it would be best if I refrained from stamping this for the time being; once you've implemented this check (there were a lot of spacing errors in the write-up, so pay attention when you implement this check) let me know and I'll check it once more and give you the stamp.