UU Victim of the Week! (Week Twenty-Seven: Contrary Serperior)

[Colbrushie]

Cobalion @ Life Orb
Ability: Justified
EVs: 252 Spd / 252 Atk / 4 HP
Jolly Nature
- Swords Dance
- Close Combat
- Iron Head
- Stone Edge / X-Scissor / Volt Switch

This is assuming he dances on the switch. Bonus points if you can get a Crunch on the switch and get the +1.

Extremespeed doesn't do a thing to 91/129 defenses even while uninvested.
+2 252+ Atk Life Orb Lucario Extreme Speed vs. 4 HP / 0 Def Cobalion: 88-105 (27.1 - 32.4%) -- 0.1% chance to 3HKO after Stealth Rock

Meanwhile, Cobalion can outspeed and hit it right back with a Close Combat, which forces the Lucario out potentially letting you get a free SD up.
252 Atk Life Orb Cobalion Close Combat vs. 0 HP / 0 Def Lucario: 530-627 (188.6 - 223.1%) -- guaranteed OHKO

Other options include CM Cobalion bluffing something that can kill Luke without 70 accuracy and Calm Minding on the switch, Rocks Cobalion getting his Rocks off all over the opponent's field, or Volt Switching to preserve momentum.

X-Scissor listed as coverage to hit Slowbro, although it still only 2HKOs even with rocks up after a Swords Dance, and 3HKOs with rocks without.

Volt Switch is self-explanatory. Can also replace Iron Head.

 

[Petrico94]

Hippowdown @ Leftovers
Ability: Sand Stream
EVs: 252 HP / 4 Atk/ 252 Def
Impish Nature
- Earthquake
- Slack Off
- Whirlwind
- Stealth Rock
Counter to luke (will put in calcs later)

+2 252+ Atk Life Orb Lucario Close Combat vs. 252 HP / 252+ Def Hippowdon: 320-376 (76.1 - 89.5%) -- guaranteed 2HKO after Leftovers recovery

Everything else is low enough but that Close Combat is going to hurt and leave 36% health at best. If you whirlwind him out you could get a good match up and slack off some of the damage but if you use earthquake you kill Lucario the same turn but give the enemy the chance to send in anything they want as a check and Hippowdon has to live with that health.

 

[pokemonisfun]

counter
Qwilfish @ Leftovers
Ability: Intimidate
EVs: 252 Def / 252 HP / 4 Atk
Impish Nature
- Waterfall
- Pain Split
- Spikes
- Thunder Wave


Lucario can only 3HKO with SR and Intimidate after a Swords Dance so Qwilfish can 2HKO first easily with Life Orb Damage and Close Combat drops. Pain Split means you can do this throughout the course of the game if the Lucario user decides to preserve Lucario. Thunder Wave and Spikes means you can give your team support too if you come in on a move under than Swords Dance because you might as well since Lucario is doing so little damage to you it becomes something like set up fodder.

 

[CoolStoryBrobat]

Alright, got the top 3 checks & counters each for SD Lucario: (No specific order)

Counters:

Gligar - Swamp Link
Sableye - Calloflochie
Qwilfish - hilarious

Checks:

Slowbro - michaeloche
Chandelure - Sleepless
Cobalion - Colbrushie

So here's the victim of next week:

It moves this week!

name: Specially based Life Orb
move 1: Draco Meteor
move 2: Dark Pulse
move 3: Superpower / Iron Tail
move 4: Fire Blast / Roost
ability: Levitate
item: Life Orb
evs: 4 Atk / 252 SpA / 252 Spe
nature: Naive / Hasty

Now remember...if a Pokemon has less than 3 complete counters, then however many it does will be listed while whatever other slots are left blank. So if you guys want to win for this week, bring your absolute best checks you got this time around. Look forward to seeing some competitive thinking this week. :]

Advance note: DO NOT MAKE A RESERVATION WITHOUT UPDATING WITHIN AT LEAST 6 HOURS. FAIL TO DO SO AND SOMEONE ELSE WILL BE ABLE TO CLAIM IT. DO NOT CHANGE YOUR RESERVATION AFTER MAKING IT, EITHER.

Doing this because I know people are gonna try to take the best mons quickly as they can, and that's to be expected. But this is also so people don't fight eachother over who reserved what and when they did yada yada yada. Hopefully this encourages people to think a bit more before reserving something for this project.

...And my mascot is a giant vampire bat. You think I won't be around within 6 hours to check up on you? THINK AGAIN

 

[Bouff]

reserving infernape as a check

what the fuck even counters this rofl

 

[CoolStoryBrobat]

what the fuck even counters this rofl

:] part of the concept

Premise of this project is to help players learn what checks and counters what in UU, part of the learning experience is realizing some things don't have absolute counters

 

[Swamp Link]

Reserving Porygon2 as the strongest counter.

Edit: Just kidding, that Draco Meteor + Superpower just barely wrecks it no matter the spread. :(

 

[SlottedPig]

name: Physically Defensive
move 1: Wish
move 2: Protect
move 3: Moonblast
move 4: Aromatherapy
ability: Aroma Veil
item: Leftovers
evs: 248 HP / 252 Def / 8 SpD
nature: Bold

Physically Defensive Aromatisse is an even better switchin to special LO Hydreigon than Florges, and that's saying a lot. Neither Draco Meteor nor Dark Pulse threaten Aromatisse. While Iron Tail is super effective, Aromatisse is physically bulky enough to only take 42.9 - 50.6%, while Fire Blast deals 41.4 - 48.8%. While this seems like a lot, Aromatisse gains 12.5% of its health back from switching in and using Protect, and Iron Tail's accuracy means that even with rocks (or any single layer of hazards) up and if Aromatisse is not holding its Leftovers it has less than a 50% chance to hit Iron Tail twice and 2HKO Aromatisse. Fire Blast will never 2HKO barring burn or crit hax, and Aromatisse isn't particularly difficult to keep healthy.

Meanwhile, Aromatisse always OHKOs back with Moonblast and can support its team with Wish or Aromatherapy. For bulkier teams in need of a physically defensive fairy, Aromatisse is even better than Florges at this job, and it also passes larger Wishes and is immune to Taunt and Encore.

 

[Wobblebuns]

Reserving Snorlax.

EDIT: I ran some quick calcs and it looks discouraging. This is not boding well for me.

 

[Jellied Eels]

Welp so I had to dig pretty deep for this one but at least I can say it's a counter :)

Togetic @ Eviolite
Ability: Serene Grace
EVs: 248 HP / 252 Def / 8 SDef
Bold Nature
IVs: 0 Atk
- Dazzling Gleam
- Roost
- Defog / Nasty Plot
- Heal Bell / Baton Pass

Let's start with the calcs :

252 SpA Life Orb Hydreigon Fire Blast vs. 248 HP / 8 SpD Eviolite Togetic: 96-114 (30.6 - 36.4%) -- 61.6% chance to 3HKO
4 Atk Life Orb Hydreigon Iron Tail vs. 248 HP / 252+ Def Eviolite Togetic: 104-125 (33.2 - 39.9%) -- 100% chance to 3HKO (which is a 23.8% chance to 2HKO if SR is up)

Meanwhile Dazzling Gleam manages not to OHKO a 100% of the time if Hydreigon is Naive which it should be :

0 SpA Togetic Dazzling Gleam vs. 0 HP / 0 SpD Hydreigon: 312-372 (96 - 114.4%) -- 75% chance to OHKO

So yeah tbh I'm pretty sure Toge is the only mon with reliable recovery that does this well vs. Hydreigon. The problem being of course that you're using Togekiss which only has a very limited niche in UU. You probably all know the issues it has (an SR weakness, the mons it switches into typically run Knock Off, lots of competition from the likes of Aromatisse, Gligar...)
The two sets I've listed are imo the only ones worth using, simply because they really aren't outclassed by anything. The Defog set is kind of a worse Aromatisse that has access to Defog - pretty straightforward imo. I personally prefer the other set because it's almost always better to use two teamslots > Defog Toge, while the BP set can be very clutch, kinda like BP Celebi but with a different set of resistances.

So yeah I'm not gonna pretend that Togekiss is a great mon but let's try not to leave that counter list too empty shall we :)

 

[Calloflochie]

Reserving forfeit button

Ok but seriously, i'm going to be using a viable mon but with a different set (and not a Fairy-type :oooo). The Pokemon I am going to highlight is Specially Defensive Suicune. Suicune has always been known as a Physical Wall, tbh it still always should be, it's typing lends itself to better deal with the Physical spectrum of the UU metagame as opposed to the Special Spectrum but luckily it can still have it's uses. The biggest problem I see with 'countering' Hydreigon is it's not necessarily about countering it's main STAB, I mean, many Pokemon can comfortably switch into Dark Pulse and Draco Meteor. What the real kicker is about Hydreigon is those nasty 3rd and 4th moveslots. Iron Tail especially just puts a huge amount of pressure onto whether or not it's safe bringing in your Florges or Aromatisse or even Granbull (which i was going to use and tbh it's worth putting in with a Spread of 252 HP / 56 Def / 212 SDef (hint) since with that spread, after SR, Hydreigon only has a 2.7% chance or something like that to 2HKO with Iron Tail or Fire Blast which when factoring in the accuracy bumps out the 2.7% chance even further basically guaranteeing a 3HKO in all circumstances. But, enough of giving everyone another set, back to Suicune. Suicune has the ability to switch into the STABs and comfortably take 2 after SR and NEVER have to worry about a stray Grass Knot or Energy Ball or whatever so basically it's a no brainer switch in. The set i'm using has a slight twist on it and that is the inclusion of Toxic, which when paired with Suicune, allows it to win CM wars vs things like Slowbro which it would otherwise be losing so still giving this set some viability outside of countering Hydreigon. But what I think the best thing about using Suicune is, that Hydreigon has only 4 Draco Meteors to use because of Pressure, so if Hydreigon wants to stay in and try to bombard Suicune, it runs out of Dracos way before Suicune is running out of rest :] Ice Beam can be used to hit Hydreigon for SE damage but it's pretty darn weak and Toxic has far more utility + it's a no brain switch in and you can basically just PP stall the Hydreigon out of Dracos if need be.

This is the set

Suicune @ Leftovers
Ability: Pressure
EVs: 252 HP / 252 SDef / 4 SAtk
Calm Nature
- Rest
- Sleep Talk
- Scald
- Toxic / Ice Beam

mfw /c/ounter takes nearly half from Draco

252 SpA Life Orb Hydreigon Draco Meteor vs. 252 HP / 252+ SpD Suicune: 175-208 (43.3 - 51.4%) -- 63.7% chance to 2HKO after Stealth Rock and Leftovers recovery
-2 252 SpA Life Orb Hydreigon Draco Meteor vs. 252 HP / 252+ SpD Suicune: 87-105 (21.5 - 25.9%) -- possible 5HKO after Stealth Rock and Leftovers recovery
So collectively it's going to be doing at best if Leftovers recovery is factored in too over 2 turns, it will take around 65% from the Dracos (if it chooses to stay in which basically means it is PP stalled out of Dracos) and Suicune can Rest off the damage :]

252 SpA Life Orb Hydreigon Dark Pulse vs. 252 HP / 252+ SpD Suicune: 109-129 (26.9 - 31.9%) -- guaranteed 4HKO after Stealth Rock and Leftovers recovery
252 SpA Life Orb Hydreigon Fire Blast vs. 252 HP / 252+ SpD Suicune: 49-58 (12.1 - 14.3%) -- possibly the worst move ever
4 Atk Life Orb Hydreigon Iron Tail vs. 252 HP / 252 Def Suicune: 35-42 (8.6 - 10.3%) -- possibly the worst move ever
4 Atk Life Orb Hydreigon Superpower vs. 252 HP / 0 Def Suicune: 104-123 (25.7 - 30.4%) -- 98.8% chance to 4HKO after Stealth Rock and Leftovers recovery

Also combinations like Dark Pulse + Draco aren't going to kill, the only way Hydreigon is going to win is if it gets a flinch with a second Dark Pulse (while getting a good roll) and then gets a good roll on Draco so y'know. Or Crit maybe but if this fucker crits, everything in the tier is getting OHKO'ed.

 

[Ununhexium]

Reserving Florges

 

[michaeloche]

Reserving Shuckle

Shuckle @ Leftovers/Chesto Berry
Ability: Sturdy/Contrary
EVs: 252 HP / 4 Def / 252 SDef
Calm Nature
-Toxic
-Infestation
-Rest
-Sleep Talk/Stealth Rock/Sticky Web/Shell Smash

Shuckle, the derpy turtle thing with the gargantuan defenses, makes for a respectable wall, and, given the right investment, laughs in the face of anything that Hydreigon can throw at it. The following is the most that Hydreigon can do to Shuckle:

252 SpA Life Orb Hydreigon Draco Meteor vs. 252 HP / 252+ SpD Shuckle: 105-125 (43 - 51.2%) -- guaranteed 3HKO after Leftovers recovery

Dark Pulse, Fire Blast, Superpower, and Iron Tail max out at 31.9, 28.6, 27.8, and 45.9% damage, respectively. That means, barring a crit, excessive hazards, being the recipient of BP boosts, or Iron Tail hax, Hydreigon cannot possibly 2HKO Shuckle. In return, Shuckle can trap Hydreigon with Infestation and whittle it away with the combined effect of that, Toxic, and LO recoil. Rest lets Shuckle keep itself healthy because hax can happen. The last slot is a bit of a toss-up, depending on what else you have on your team. Contrary can turn Iron Tail hax to your advantage, if you're so inclined, in addition to Shell Smash boosts.

The only thing keeping Shuckle from being a true counter is hazards. Draco Meteor has a very small chance to OHKO Shuckle after SR and 3 layers of Spikes. This means Shuckle is a check to Hydreigon.

 

[pokemonisfun]

but if you factor in sr it cant switch in on dark pulse or iron tail so its a bad counter michaeloche

 

[michaeloche]

but if you factor in sr it cant switch in on dark pulse or iron tail so its a bad counter michaeloche

Duly noted, although Dark Pulse is easier to switch into. Fixing.

 

[Inspirited]

Solid as a ro- aw furget it

Regirock @ Assault Vest
Ability: Clear Body
EVs: 80 HP / 252 Atk / 176 SpD
Careful nature
- Drain Punch
- Stone Edge
- Earthquake
- Explosion

Soft Check

whatisthisIdon'teven Wreck? This just looks like another random Assault Vest user that shouldn't be mentioned over Rhyperior ect. but if it means checking LO Hydreigon, then I think this thing has a workable niche. The EVs are actually to avoid any 2HKO from Draco Meteor + Superpower after Stealth Rock whilst avoiding putting too much investment in HP so you get better overall recovery with Drain Punch. Drain Punch is always a 2HKO on non-Roost (because of its own Life Orb) and even Roost variants will only be feeding Regirock HP as they are forced to continually Roost. If they Superpower, the Explosion is an OHKO if you feel like being flashy, although losing Regirock in the process is a bummer. The only downside to this set really is that Regirock cannot use its fantastic support options and it makes it so it's last slot is filler above all else.

 

[pokemonisfun]

how about Assault Vest Machamp as a counter?

Machamp @ Assault Vest
Ability: No Guard
EVs: 252 HP / 252 SDef / 4 Atk
Adamant Nature
- Dynamic Punch
- Stone Edge
- Knock Off
- Bullet Punch

The EVs means Draco Meteor isn't a 2HKO even before you factor the drop in special attack so you can take one comfortably followed by any of the moves Hydreigon has really except something like Outrage but that is not listed. Adamant natures gives you the most stat boost since attack is naturally your highest stat and the rest of the moves gives coverage except Bullet punch which lets you pick off sash users such as Azelf or Froslass. The only problem is lack of recovery but Machamp at full health is still a solid counter for at least one time. Dynamic Punch is an OHKO all the time if Hydreigon has taken any damage before such as Life Orb.

 

[JMach]

Defensive Aromatisse completely shuts this down haha - not that it's even close to being better than the specially defensive set but it's still a hard counter.

 

[RufflesPro]

Reserving Registeel as a counter.

Registeel @ Leftovers
Ability: Clear Body
EVs: 252 HP / 252 SDef / 4 Def
Careful Nature
- Rest
- Toxic
- Sleep Talk
- Seismic Toss / Iron Head
​

252 SpA Life Orb Hydreigon Fire Blast vs. 252 HP / 252+ SpD Registeel: 164-195 (45 - 53.5%) -- 1.2% chance to 2HKO after Leftovers recovery
0 Atk Life Orb Hydreigon Superpower vs. 252 HP / 0 Def Registeel: 164-195 (45 - 53.5%) -- 1.2% chance to 2HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Dark Pulse vs. 252 HP / 252+ SpD Registeel: 90-107 (24.7 - 29.3%) -- possible 5HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Draco Meteor vs. 252 HP / 252+ SpD Registeel: 73-86 (20 - 23.6%) -- possible 6HKO after Leftovers recovery

The only way Hydreigon would win if he got lucky as fuck and got dat 1.2% chance or rocks are up and gets that 38% chance to 2HKO.

All you need to do to win is get 1 toxic through Sleep Talk, S-Toss or Iron Head wear down Hydra faster if it runs Roost. It's not the best counter, but if anything, it's a really good check.

 

[Flygoner818]

COUNTER lol but actually

Marill @ Eviolite
Ability: Huge Power
EVs: 252 HP / 252 Def / 4 SDef
Adamant Nature
- Waterfall
- Play Rough
- Knock Off
- Toxic / Charm / Encore

Before all the haters come after me:

252 SpA Life Orb Hydreigon Dark Pulse vs. 252 HP / 4 SpD Eviolite Marill: 95-113 (27.6 - 32.8%) -- guaranteed 4HKO
252 SpA Life Orb Hydreigon Fire Blast vs. 252 HP / 4 SpD Eviolite Marill: 87-103 (25.2 - 29.9%) -- guaranteed 4HKO
0 Atk Life Orb Hydreigon Iron Tail vs. 252 HP / 252 Def Eviolite Marill: 78-92 (22.6 - 26.7%) -- 30.4% chance to 4HKO

0+ Atk Huge Power Marill Play Rough vs. 0 HP / 0 Def Hydreigon: 304-360 (93.5 - 110.7%) -- 56.3% chance to OHKO

I think the calcs speak for themselves. I know he's not super-viable in UU, but if we're looking for pure counters, Marill has everything it needs. Doesn't take super-effective damage from anything Hydreigon can throw at it. Plus, it's got enough physical bulk and a decent support move pool to not be complete deadweight against some other threats, all of which it can OHKO/2HKO after SR:

Hide

+2 252+ Atk Fletchinder Acrobatics (110 BP) vs. 252 HP / 252 Def Eviolite Marill: 213-252 (61.9 - 73.2%) -- guaranteed 2HKO
252 Atk Mega Absol Knock Off (97.5 BP) vs. 252 HP / 252 Def Eviolite Marill: 70-83 (20.3 - 24.1%) -- guaranteed 5HKO
252 Atk Mega Aerodactyl Stone Edge vs. 252 HP / 252 Def Eviolite Marill: 135-159 (39.2 - 46.2%) -- guaranteed 3HKO
252 Atk Mega Heracross Pin Missile (5 hits) vs. 252 HP / 252 Def Eviolite Marill: 105-130 (30.5 - 37.7%) -- approx. 90.5% chance to 3HKO
252+ Atk Life Orb Honchkrow Brave Bird vs. 252 HP / 252 Def Eviolite Marill: 216-255 (62.7 - 74.1%) -- guaranteed 2HKO

 

[CoolStoryBrobat]

Does anybody believe in checks? Lol. The creativity level of this thread is unreal. People come up with stuff I never would have even thought of, and I actually think that's amazing. But examples by Swamp Link and Wobblebuns about Snorlax and P2 being inefficient...still renders them as possible checks, lol. Remeber Hydreigon isn't capable of running all 6 moves at the same time...

"-To be considered a check, a Pokemon must be able to switch into at least one but not all of the opponent's moves under normal battle conditions, including taking damage from Stealth Rock, and reliably KO the opponent before the counter is KOed itself" - The OP

Keep 'em coming :]

 

[~BLOOM~]

I'm new to smogon forums, might be a smogonite idk. will add sprites and other stuff later when my computer is functional.



Infernape. Now this is not your straight up iron fist flare blitz all the things infernape, it's take no bullcrap infernape. One day, I got tired of Hydreigon's shit and made this. (funny part is I use hyd lol don't use this set on me) AV Nape. I know. This idea is shit. But hear me out. Infernape scares hydreigon the fuck out right? WHAT WILL YOU DO if that nightmare can switch in on you all damn day with wish support? scary right? so here it is.

Infernape @ Assault Vest
Ability: Iron Fist
EVs: 52 Atk/72 Def/132 Sdef/252 Spe
Jolly Nature
-Flare Blitz/Fire Punch
-U-Turn
-Close Combat
-Will-O-Wisp





I bet you guys think I'm a scrub and I am, but test this out for yourself. It takes every one of Mixed Hyd's moves are taken by this set.

Hide

0 Atk Life Orb Hydreigon Superpower vs. 0 HP / 72 Def Infernape: 140-166 (47.7 - 56.6%) -- 88.3% chance to 2HKO

252 SpA Life Orb Hydreigon Draco Meteor vs. 0 HP / 132 SpD Assault Vest Infernape: 200-238 (68.2 - 81.2%) -- guaranteed 2HKO

252 SpA Life Orb Hydreigon Dark Pulse vs. 0 HP / 132 SpD Assault Vest Infernape: 62-74 (21.1 - 25.2%) -- 0% chance to 4HKO

252 SpA Life Orb Hydreigon Fire Blast vs. 0 HP / 132 SpD Assault Vest Infernape: 57-68 (19.4 - 23.2%) -- possible 5HKO

And hyd is nearly ohkod by 52 attack close combat. In advance, this is a CHECK and should not be judged as a counter in any way, shape or form. (Albeit, a shaky check.)
I hope you found my set extremely creative and terrible, but vote for it anyway.

deuces bros, see you on the ladder

EDIT: Bouffalant, you didn't post in 6 hours so infernape is mineeeeee. Rules are a bitch.

 

[pokemonisfun]

Reserving Registeel as a counter.

Registeel @ Leftovers
Ability: Clear Body
EVs: 252 HP / 252 SDef / 4 Def
Careful Nature
- Rest
- Sleep Talk
- Iron Head
- Thunder Wave / Toxic
​

252 SpA Life Orb Hydreigon Fire Blast vs. 252 HP / 252+ SpD Registeel: 164-195 (45 - 53.5%) -- 1.2% chance to 2HKO after Leftovers recovery
0 Atk Life Orb Hydreigon Superpower vs. 252 HP / 0 Def Registeel: 164-195 (45 - 53.5%) -- 1.2% chance to 2HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Dark Pulse vs. 252 HP / 252+ SpD Registeel: 90-107 (24.7 - 29.3%) -- possible 5HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Draco Meteor vs. 252 HP / 252+ SpD Registeel: 73-86 (20 - 23.6%) -- possible 6HKO after Leftovers recovery

The only way Hydreigon would win if he got lucky as fuck and got dat 1.2% chance or rocks are up and gets that 38% chance to 2HKO.

Thunder Wave + Iron Head means that between misses, paras, and flinches you'll easily stall Fire Blast. Toxic wears down Hydra easier though. Rest + Sleep Talk for recovery.

given the fact sr needs to be up to be called a counter Registeel cannot switch in either Superpower or Fire Blast or else the next Fire Blast can KO not to mention even if you do live and Thunder Wave Iron Head will take a long tim eto kill and Hydreigon can STILL kill you first before you kill it especially if Hydreigon runs Roost

Registeel is a bad counter

 

[RufflesPro]

given the fact sr needs to be up to be called a counter Registeel cannot switch in either Superpower or Fire Blast or else the next Fire Blast can KO not to mention even if you do live and Thunder Wave Iron Head will take a long tim eto kill and Hydreigon can STILL kill you first before you kill it especially if Hydreigon runs Roost

Registeel is a bad counter

No. With rocks it's only 38% [Pokemon rounds down] to 2HKO Registeel. So even if you switch on a Superpower or a Fire Blast, if you don't get unlucky and live, you T-wave and Rest. Then Sleep Talk for 2 turns and the Rest again. Keep doing that. Also, even if it takes long time to kill Hydra and even if it Roosts, as I said it only has 8 Fire Blasts, You live 2 and keep healing, not to mention missing is a thing. So even if it runs Roost, you can kill it, eventually, it'll just take a long time.

But you have a point, so I'mma edit it to only Toxic, because toxic wins, all you need to do is get 1 toxic through sleep talk.

It's not the best counter, but it's an OK counter, at the very least it's a very good check.

 

[Swamp Link]

Not quite as manly as Marill, but presenting this as a check:

Cobalion @ Lum Berry
Ability: Justified
EVs: 252 Spd / 252 Atk / 4 HP
Jolly Nature
- Swords Dance
- Close Combat
- Iron Head
- Stone Edge

Alright, so Cobalion can switch into any move from Hydreigon except Fire Blast, and either boost up if you think it's going to switch and threaten to sweep, or just nail it and OHKO with Close Combat. Swords Dance is its most common set, but you could also run a Stealth Rock set with Volt Switch if you so desire. Anyway, this thing fits the definition of a check pretty perfectly, it switches into 3/4 of Hydreigon's moveset, outspeeds, and OHKOes. Calcs for each move are below.

252 SpA Life Orb Hydreigon Dark Pulse vs. 4 HP / 0 SpD Cobalion: 109-129 (33.6 - 39.8%) -- 20.8% chance to 3HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Draco Meteor vs. 4 HP / 0 SpD Cobalion: 175-207 (54 - 63.8%) -- guaranteed 2HKO after Leftovers recovery
4 Atk Life Orb Hydreigon Superpower vs. 4 HP / 0 Def Cobalion: 190-224 (58.6 - 69.1%) -- guaranteed 2HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Fire Blast vs. 4 HP / 0 SpD Cobalion: 398-471 (122.8 - 145.3%) -- guaranteed OHKO :(

252 Atk Cobalion Close Combat vs. 0 HP / 0 Def Hydreigon: 336-396 (103.3 - 121.8%) -- guaranteed OHKO

Sure, people are all on the Lucario train for a Steel/Fighting-type because that is stronger and has Extremespeed, but Cobalion is faster and has better bulk, so it's still viable.