Gen 6 Victim of the Week - ORAS Edition

[xDesch]

Approved by the illustrious Sweep | OP stolen by the kind Aragorn the King
Art by the amazing justinjiaxinghu​

Every generation is different and the metagame is constantly changing. While the viable pokemons may vary, the same playstyles, strategies and problems will be encountered along the way. Each week a Pokemon, or a “victim” as we call it, will be chosen and it is your job to find the best, most efficient and practical checks and counters to the victim of the week.

This project aims to help players to find out and know which pokes to be expected and how to efficiently handling. We hope to find new and maybe innovative ways to handle pokes that can make it possible to find new and healthy teambuilding options in the future. Maybe you will be inspired to build a new team around a certain Pokemon?

Procedure

1. Every round, I will nominate a Pokémon for discussion. Within one week's time, you guys will have the ability to discuss and nominate various Pokémon that you think can check or maybe even counter the victim of the week. Note that the moves, EV’s and Nature on the victim of the week is not set in stone, so the more prepared your check/counter is to other variations, the better it is.

2. After the deadline, I will choose the best checks/counters. Should there be a lot of nominations, I will discuss my choices with other skilled players to ensure the selections are not biased and that all nominations have been considered thoroughly. Note that while checking the victim of the week is important, it is usually better to focus on having a set that works good in the metagame or has a decent niche.

3. The results will be archived with an expanded description and the process will continue week after week.

4. We will continue where the old thread stopped.

Rules

1. When nominating your check/counter please include:

- Name of the Pokémon
- Check or Counter
- Short Description as to why you chose this particular Pokémon
- Set(s) that work well against the victim of the week

2. Follow the definitions for checks, by Aragorn the King, and counters, by MattL:

Pokémon A checks Pokémon B if Pokémon A can win every time when switching into at least one of Pokemon B's attacks, without factoring in hax.

Pokémon A counters Pokémon B if Pokémon A can manually switch into Pokémon B and still win every time, even under the worst case scenario, without factoring in hax.

3. When giving checks, please follow the advice of alexwolf:

We are not looking for revenge killers, but for checks that are able to switch into the Pokemon in question at least once, and of course counters

4. Check if somebody has reserved a Pokémon before posting.

5. From Friday - Sunday, each person is limited to (reserving and thus) nominating ONE Pokemon. From Monday - Thursday, you can no longer reserve any Pokemon, and every other unfinished reservation will be canceled. You can submit as many checks/counters you want.

you may nominate as many as you want, including additional sets of already nominated checks/counters. You are not allowed to reserve any poke from here on,

6. Helping each-other is encouraged, but please try to be nice!

7. No SHITTY gimmicks!

8. Have Fun!

Archive

Archive
Double Dance Primal-Groudon
Checks/Counters: Groudon (WreckDra) Latios (Halcyon.) Flygon (Jibaku)

Calm Mind Primal-Kyogre
Checks/Counters: Ludicolo (DSM01) Palkia (smlj) Rayquaza (Jibaku)

Dragon Dance Mega-Salamence
Checks/Counters: Dialga (Nayrz) Lugia (brokenwings) Skarmory (Mega-Swampert)

Calm Mind Latios
Checks/Counters: Arceus-Dark (ZoroarkForever) Klefki (Steeljackal<3) Aegislash (Hack)

Geomancy Xerneas
Checks/counters: Groudon-Primal (Steeljackal<3) Klefki (PoweredByRevenge) Aegislash (Level 56)

Calm Mind Arceus-Dark
Checks/Counters: Clefable (NotAGymLdr) Arceus-Fairy (based n bad) Ho-Oh (Level 56)

Extreme Killer Arceus-Normal
Checks/Counters: Yveltal (DSM01) Skarmory (based n bad) Clefable (brokenwings) Sableye (Jibaku) Arceus-Ghost (haxiom)

Life Orb Ho-Oh
Checks/Counters: Stealth Rock (PISTOLERO) Arceus-Rock (steelphoenix) Rhyperior (-Leon-)

Life Orb Darkrai
Checks/Counters: Ho-Oh (Mr.378) Klefki (based n bad) Xerneas (Unwanted)

Calm Mind Mega Diancie
Checks/Counters: Ferrothorn (xDesch) Arceus-Ground (Dilwar) Kyogre-Primal (PoweredByRevenge)

Swords Dance Arceus-Ground
Checks/Counters: Kyogre-Primal (Nayrz) Giratina-O (based n bad) Lugia (DSM01)

Calm Mind Mewtwo
Checks/Counters: Sableye-Mega (Dilwar) Wobbufet (xDesch) Aegislash (haxiom)

Life Orb Yveltal
Checks/Counters: Arceus-Fairy (based n bad) Xerneas (haxiom) Arceus-Rock (Level 56)

3 Attacks Mega Mewtwo X
Checks/Counters: Sableye (based n bad) Aegislash (GnralLao) Arceus-Ghost (haxiom)

Power-Up Punch Mega Kankaskhan
Checks/Counters: Sableye (Level 56) Arceus-Ghost (haxiom) Ferrothorn (Mr.378)

Hazard Lead Deoxys-Speed
Checks/Counters: Sableye SparksBlade Cloyster TheAzumaKiller Smeargle Polonium209

Swords Dance Mega-Lucario
Checks/Counters: Giratina-O Polonium209 Lugia Random Passerby Arceus-Ground Level 56

Super Viable All-Out Attacker Metagross
Checks/Counters: Scizor Haruno Arceus-Dark Astroboy Arceus-Ghost TheAzumaKiller

Double/Dragon Dance Rayquaza
Checks/Counters: Arceus-Rock Lord Abbadon Arceus-Fairy Random Passerby Lugia GnralLao

Shaymin-Sky
Checks/Counters: Mega-Mewtwo-Y Sweep Mega-Gengar - Level 56 Latias Lord Abbadon

Dialga
Checks/Counters: Arceus-Ground Dragon God Red Arceus-Dark GnralLao Mega-Tyranitar RandomBro

Sowrds Dance Excadrill
Check/Counters: Skarmory Dragon God Red Arceus-Ground Level 56 Landorus-Therarian steelphoenix Giratina-Origin GnralLao Rayquaza Random Passerby

Arceus-Ghost
Checks/Couners for...
SD Variant: Darkrai steelphoenix/Sweep Arceus-Dark WreckDra Yveltal Random Passerby
CM Variant: Ho-Oh steelphoenix/Level 56 Clefable GnralLao Blissey Polonium209

Deoxys-Attack
Checks/Counters: Mega-Sableye Tenefix Mega-Scizor GnralLao Mega-Slowbro Astounded

Mega-Mawile
Checks/Counters: "Everything" by steelphoenix

Mega-Gengar
Checks/Counters: Blissey by steelphoenix, Scizor by GnralLao and Giratina by Half of Two

Hall of Fame

Hall of Fame

2 - WreckDra
1 - Halcyon.
3 - Jibaku
1 - smlj
3 - DSM01
2 - Nayrz
1 - Mega-Swampert
2 - brokenwings
1 - Hack
6 - steelphoenix
1 - ZoroarkForever
2 - PoweredByRevenge
8 - Level 56
6 - based n bad
1 - NotAGymLdr
4 - haxiom
1 - PISTOLERO
1 - -Leon-
1 - Unwanted
2 - Mr.378
2 - Dilwar
2 – xDesch
7 - GnralLao
3 - Polonium209
2 - TheAzumaKiller
1 - SparksBlade
4 - Random Passerby
1- Haruno
1- Astroboy
2- Lord Abbadon
2- Sweep
2- Dragon God Red
1- RandomBro
1- Tenefix
1- Astounded
1- Half of Two

Week 28: Giratina-Origin:

Giratina-Origin @ Griseous Orb
Ability: Levitate
EVs: ???
??? Nature
- Shadow Force
- Shadow Ball
- Dragon Tail
- Shadow Sneak
- Dragon Claw
- Will-O-Wisp
- Defog
- Rest

Others: HP Fire, Destiny Bond, Stone Edge, Earthquake, Aqua Tail, Substitue, Shadow Claw, etc.

 

[haxiom]

Reserving Ghostceus

EDIT:

Arceus-Ghost
Counter

Arceus-Ghost @ Spooky Plate
Ability: Multitype
EVs: 248 HP / 8 Def / 252 Spe
Timid Nature
IVs: 0 Atk
- Recover
- Judgment
- Will-O-Wisp / Focus Blast
- Defog / Calm Mind

Yeah so in short, you are immune to Mega Kangaskhan's Fake Out, Power-Up Punch, and Return, and can outspeed and burn it easily or hit it hard with Focus Blast (though you need prior damage to get any KOs) if you are Calm Mind or something. Regarding the spread, you could obviously run like Bold 96 Speed which specifically outspeeds Adamant Kangaskhan for the purposes of this project, but honestly I just put in the general best spread. With Defog, always run Will-O-Wisp, but Calm Mind can run either that or Focus Blast. Defog offers teams important support, but Calm Mind is probably immediately better vs Mega Kangaskhan because it poses a direct threat to Kangaskhan's team. You could potentially lose it the opponent gets a bunch of drops, or if Will-O-Wisp or Focus Blast misses assuming that they predict you and Crunch on the turn you switch in; however, hax is never taken into account for deciding counters. Here are some calculations:

Calculations

Mega Kangaskhan --> Arceus-Ghost

252+ Atk Parental Bond Mega Kangaskhan Crunch vs. 248 HP / 8 Def Arceus-Ghost: 237-282 (53.4 - 63.6%) -- guaranteed 2HKO
252+ Atk Parental Bond burned Mega Kangaskhan Crunch vs. 248 HP / 8 Def Arceus-Ghost: 118-141 (26.6 - 31.8%) -- guaranteed 4HKO
252+ Atk Parental Bond Mega Kangaskhan Crunch vs. 248 HP / 164+ Def Arceus-Ghost: 189-225 (42.6 - 50.7%) -- 2.3% chance to 2HKO

Arceus-Ghost --> Mega Kangaskhan

0 SpA Arceus-Ghost Focus Blast vs. 0 HP / 0 SpD Mega Kangaskhan: 202-238 (57.5 - 67.8%) -- guaranteed 2HKO

 

[Level 56]

Mega-Sableye (Counter)

Sableye-Mega @ Sablenite
Ability: Magic Bounce
EVs: 248 HP / 252 Def / 8 SpD
Impish Nature
- Protect
- Foul play
- Will-O-Wisp/Metal Burst/Toxic
- Recover

Mega-Sableye is a solid counter to mega-kangaskhan just like its regular form was a solid counter to kangaskhan in XY. Thanks to its nice bulk and ghost typing there is no way kangaskhan can win vs Sableye. Foul play 2HKO's kangaskhan.

 

[GnralLao]

Skarmory as a Counter

Skarmory @ Leftovers
Ability: Sturdy
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
- Spikes
- Roost
- Whirlwind
- Taunt / Toxic

Thanks to its Steel/Flying type and excellent physical bulk, Skarmory avoids being 2HKOed by MegaKhan. Skarmory can also Whirlwind MegaKhan away before it sets up to +2 (or right after it does so) and beyond. Moreover, it has relaible recovery via Roost to stay healthy throughout its matchups, Spikes to punish opposing switch-ins (great with Whirlwind for accumulating chip damage) and Taunt to better pressure opposing hazard setters and Defog users such as support Arceus variants on the switch-in. Toxic can be used in the slot to actually do something back to MegaKhan aside from Spikes.

Calcs

252+ Atk Parental Bond Mega Kangaskhan Fake Out vs. 252 HP / 252+ Def Skarmory: 30-36 (8.9 - 10.7%) -- possible 9HKO after Stealth Rock
252+ Atk Parental Bond Mega Kangaskhan Power-Up Punch vs. 252 HP / 252+ Def Skarmory: 40-48 (11.9 - 14.3%) -- possible 7HKO after Stealth Rock
252+ Atk Parental Bond Mega Kangaskhan Crunch vs. 252 HP / 252+ Def Skarmory: 79-94 (23.6 - 28.1%) -- guaranteed 4HKO after Stealth Rock
+2 252+ Atk Parental Bond Mega Kangaskhan Crunch vs. 252 HP / 252+ Def Skarmory: 159-187 (47.6 - 55.9%) -- guaranteed 2HKO after Stealth Rock (PuP + Crunch doesn't KO after SR and MegaKhan gets phazed away by Skarm before it's KOed)

 

[Sweep]

Reserving anything with Will-O-Wisp

Giratina @ Leftovers
Ability: Pressure
EVs: 248 HP / 252 Def / 8 Spe
Bold Nature
- Will-O-Wisp
- Rest
- Sleep Talk
- Dragon Tail

This Pokemon is also terrible, but is immune to Power-up Punch and isn't 2HKOed by Crunch. Therefore, it's a good check. Good luck trying to fit this on a team though!

 

[Minority]

Reserving the entire metagame
Garchomp as a check

Garchomp @ Rocky Helmet
Ability: Rough Skin
EVs: 248 HP / 8 Atk / 252 Def
Nature: Impish
~ Stealth Rock
~ Toxic
~ Earthquake
~ Outrage

This is a set I think I tried using like one time in a test battle just to experiment; canman98 and I were playing around with it a few weeks ago. This set needs optimization and I never got around to working on it, but the combination of Rocky Helmet and Rough Skin can really hinder Mega Kangaskhan. You do lose if Kanga goes to +2 as you come in since Return does enough to KO, but you can just double switch to something else to finish; really this thing is just for punishing use of Fake Out. This set also "checks" Mega Salamence, Primal Groudon, and a few other things. Like I said needs to be optimized but thought it would be fun to share anyways.

 

[Mr.378]

Ferrothorn @ Rocky Helmet
Ability: Iron Barbs
EVs: 252 HP / 6 Atk / 252 Def
Relaxed Nature
IVs: 0 Spe
- Gyro Ball
- Spikes
- Leech Seed
- Stealth Rock

PuP Mega Kanga, the most threatening pokemon in the entire meta, shutters at the thought of this monstrosity. Ferrothorn, the massive tank that it is can completely exploit Kanga's brilliant moveset by simply existing. Every time that Kangaskhan hits ferrothorn it will lose 30+ percent of it's health. With the brilliant tactical desision to run no super effective moves other then Pup, earthquake, of anything else effective it will go down quite quickly as ferro does whatever as Kanga punches itself to death.

+2 252 Atk Parental Bond Mega Kangaskhan Crunch vs. 252 HP / 252+ Def Ferrothorn: 153-180 (43.4 - 51.1%) -- guaranteed 3HKO

The best case scenario for this Kanga as it needs to Pup then crunch twice which will kill it on its own. Ferro meanwhile can get up a few layers of spikes for a relatively low cost.

 

[Inspirited]

Hugh Jackman (Mewtwo) @ Mewtwonite X
Ability: Pressure
EVs: 252 Atk / 4 Def / 252 Spe or 176 HP / 76 Atk / 4 Def / 252 Spe
Jolly Nature
- Low Kick
- Taunt
- Earthquake
- Ice Punch

Normally, cats are used to take care of you basic household rodent problems. When the extra large rodents of Australia begin trespassing, you need more. The Psycho Cats are who you must contact for problems involving Australian pests. They all have ways obliterating them, but none of the Psycho Cats do this better than Hugh Jackman: The X Cat. His kicks will fell Kangaroo quickly and precisely, no matter what. He is also able to deal with the pests that get crafty and attempt to throw mighty Sucker Punches that would fell the rest of his brethren. In fact, should a Kangaroo Fake him Out, he will only strike faster after flinching slightly. He can also take any one beating from this extremely large and dangerous rodent just to strike back with a Kick to KO it. amazing nickname idea from TonyFlygon

I will add in calcs later, but all that needs to be known is that MMX OHKOes Kang with LK and it can take any one hit bar crits from Kanga​

 

[SG-58]

Reserving Gengar-Mega

Gengaritis (Gengar) @ Gengarite
Ability: Levitate (Shadow Tag)
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature
- Taunt
- Destiny Bond
- Sludge Wave
- Focus Blast

Gengar is a check - it can switch into anything not named Crunch (gotta love immunities) and either Focus Blast to KO Kanga (with a little prior damage) or just Destiny Bond it down.

252 SpA Gengar Focus Blast vs. 0 HP / 0 SpD Mega Kangaskhan: 262-310 (74.6 - 88.3%) -- 6.3% chance to OHKO after Stealth Rock

252+ Atk Parental Bond Mega Kangaskhan Crunch vs. 4 HP / 0 Def Gengar: 423-498 (161.4 - 190%) -- guaranteed OHKO

 

[NabboCheTesta]

auto-roasting chicken as a check

Blaziken@Life Orb/Blazikenite
Ability: Speed Boost
EVs: 252 Atk / 252 Spe / 4 Def
Adamant/Jolly Nature
- Protect
- Low kick
- Flare Blitz
- Knock Off/something

In 1v1 situation, protect and pwn with low kick.
You can switch into Crunch or PuP if you feel ballsy.


252 Atk Mega Blaziken Low Kick (100 BP) vs. 0 HP / 4 Def Mega Kangaskhan: 380-450 (108.2 - 128.2%) -- guaranteed OHKO
(380, 386, 390, 396, 398, 404, 408, 414, 416, 422, 426, 432, 434, 440, 444, 450)

And this is the weakest one.
It also can take Sucker Punch if needed.

 

[Iura]

Reserving Aegislash

 

[Random Passerby]

Reserving Yveltal as a check.


Yveltal @ Leftovers
Ability: Dark Aura
EVs: 248 HP / 252 Def / 8 SpD
Impish Nature
- Foul Play
- Taunt
- Sucker Punch
- Roost

Can switch into any attack except Return and KO Kangaskhan with Foul Play + Sucker Punch.

 

[Polonium209]

Aight I just started testing this thing today so I don't know much about it, but it can definitely kill Kang.

Arceus Fighting @ Fist Plate
Ability: Multitype
EVs: 252 HP / 144 Spa (or 144 Def) /112 Spe
Timid Nature
-Judgment
-Thunder Wave
-Shadow Ball/Stone Edge
-Recover

It can switch into any attack and scare it out or kill it with Judgment. Fightceus takes absolutely nothing from dark type attacks, so no worries on getting finished off by Sucker Punch. Thunder Wave is mandatory to cripple common switchins such as Latis and Mewtwo, as well as Kang if it stays in. Shadow Ball hits ghost types and Stone Edge hits the bird. Unfortunately, even with 144 Def, Fightceus has a high chance to die to +2 return, unlike some of the other Pokes listed here.

Calcs===============================
144 SpA Fist Plate Arceus-Fighting Judgment vs. 0 HP / 0 SpD Mega Kangaskhan: 342-404 (97.4 - 115%) -- 81.3% chance to OHKO

252+ Atk Parental Bond Mega Kangaskhan Return vs. 252 HP / 0 Def Arceus-Fighting: 229-270 (51.5 - 60.8%) -- guaranteed 2HKO

252+ Atk Parental Bond Mega Kangaskhan Sucker Punch vs. 252 HP / 0 Def Arceus-Fighting: 60-70 (13.5 - 15.7%) -- possible 7HKO

 

[xDesch]

On to Week 16!
This time we'll do something slightly different. Instead of simply beating a poke 1 on 1, I'd like you to come up with something that would prevent it from doing it's job, setting up entry hazards, efficiently. Basically I want you to come up with good anti-leads to this week's victim of the week: Deoxys-Speed

Deoxys-Speed @ Focus Sash
Ability: Pressure
EVs: 252 Def / 4 Atk / 252 Spe
Timid / Jolly Nature
- Stealth Rock
- Taunt
- Spikes
- Knock Off / Skill Swap

Since this is obviously a lead, you are allowed to assume that you don't have to switch in on this guy, and just focus on anti-leading him instead. I also want to stress what Haxiom said about giving "the best general set", as it is much better to have that, compared to having anything that is specifically designed to beat the victim of the week (and nothing else in the meta).
The OP will be updated at a later time.

 

[SparksBlade]

Reserving Mega Sableye

 

[Mr.378]

Mewtwo-Mega-X @ Mewtwonite X
Ability: Steadfast
EVs: 248 HP / 252 Def / 8 SpD
Bold Nature
- Magic Coat
- Taunt
- Recover
- Foul Play

Anti leadtwo X! This shuts down anything Deoxys-S can try and do with magic coat and taunt while 2hkoing with foul play. Recover heals if needed even though Knock off does zero.

 

[SparksBlade]

Reserving Mega Sableye

Sableye @ Sablenite
Ability: Prankster / Stall
EVs: 248 HP / 252 Def / 8 SpD
Impish Nature
- Fake Out
- Foul Play
- Recover
- Taunt / Metal Burst / Toxic

Your generic Mega Sableye: Fake out breaks sash, Foul Play 2HKOs, Recover is recovery, last move is a toss up. But there's a catch!!
Bet most of you didn't check the ability n_n If you're feeling brave, just don't mega first turn and let it skill swap as you foul play. tadah! Threat neutered it ain't getting rocks up cos now, even with that blistering speed, it's slower than your base 20 diamond-eating mega, or maybe it's moving faster but doesn't matter cos you're gonna mega next turn. Most of the times Deo-S won't try to set rocks on a sab cos no HO team would like rocks on its side, so more often than not it will pay off. I hope this made sense to you all.
Someone link me it's sprite pls. Sprites are cool.

 

[Level 56]

Reserving Cloyster

 

[GnralLao]

Deoxys-Defense @ Mental Herb
Ability: Pressure
EVs: 248 HP / 8 Def / 252 SpD
Calm Nature
IVs: 0 Atk
- Stealth Rock
- Spikes
- Taunt
- Thunder Wave

With its great bulk and a Mental Herb, this Deoxys-D lead set can lay at least two layers of entry hazards while its combination of Taunt + Thunder Wave + Mental Herb limits Deoxys-S to set up a single layer of entry hazards at most and renders it useless afterwards. If Deoxys-S uses Taunt on its first turn, Mental Herb will protect Deoxys-D and the latter can simply use Thunder Wave and Taunt on the following turn, preventing Deoxys-S from laying any entry hazards and making it complete dead weight for its team. In the event that Deoxys-S decides to set up SR/Spikes on the first turn, the same scenario happens with the only differences being Deoxys-D still having its Mental Herb and SR/one layer of Spikes on its side. Moreover, Deoxys-D doesn't really care about Deoxys-S' last moveslot since Knock Off only 5HKOes it at best and it's "immune" to Skill Swap (same ability).

Final result: either way, Deoxys-S has been paralyzed, taunted and layed a single layer of entry hazard at most while Deoxys-D is untouched (unless Knocked Off) and can freely set up entry hazards of its own.

Here you go SparksBlade http://play.pokemonshowdown.com/sprites/xyani/
And for shinies and past gens: http://www.pokestadium.com/tools/sprites

 

[Aberforth]

Reserving Forretress.

 

[Polonium209]

Smeargle is a great anti-lead to Deo; this version practically guarantees hazards off the field with no 50/50s.

Smeargle @ Focus Sash
Ability: Own Tempo
EVs: 252 Def / 4 SpD / 252 Spe
Jolly Nature
-Nuzzle
-Rapid Spin
-Taunt
-Sticky Web

Nuzzle paralyzes Deo through Taunt and also isn't bounced back by Magic Coat. Smeargle can then spin any hazards away and proceed to set up his own. It's possible that Deo will chuck rocks and then switch into a spinblocker like Gengar, but even in the worst case Deo gets up only one layer of hazards.

 

[NabboCheTesta]

OYSTER COMING THROUGHT!!!
Cloyster is a counter

Cloyster @ Icicle Plate / Focus Sash
Ability: Skill Link
EVs: 252 Atk / 4 Def / 252 Spe
Adamant / Jolly Nature
- Rapid Spin
- Shell Smash
- Spikes / Toxic Spikes / whatever
- Icicle Spear

I will give a clearer explanation here:
If he tries hazards, you spin them away.
He cannot touch you ( the worst thing it can do is skill swap skill link lmao )
You can then happily set spikes up or Shell Smash.
If you get a smash you can destroy half of the meta ( even spdef aegislash, which resists, takes a big toll ).
If you get spikes up, your enemies will be hard-pressed to find a way to spin / defog.

TL, DR: Cloyster counters the shit out of deo-s aka the latter cannot do anything.

 

[Random Passerby]

Scolipede @ Focus Sash
Ability: Speed Boost
EVs: 252 Atk / 252 Spe / 4 whatever
Jolly Nature
- Pin Missile
- Spikes / Toxic Spikes
- Protect / Toxic
- Endeavor

Protect allows you to prevent the Taunt and be faster than Deoxys-S. Then, you can KO it with Pin Missile, limiting it to 1 entry hazard. You can also use your Speed to get up Spikes or Toxic Spikes. Focus Sash allows you live a hit and Endeavor the opponent. You can also forgo Protect for Toxic if you want.

 

[haxiom]

Level 56's reservation is void now that it is Monday. Sorry man.

Mega Diancie
Check

Diancie @ Diancite
Ability: Clear Body --> Magic Bounce
EVs: 80 Atk / 252 SpA / 176 Spe
Naive Nature
- Moonblast
- Diamond Storm
- Earth Power
- Protect / Heal Bell / Calm Mind

Mega Diancie is a good check to Deoxys-S. Magic Bounce pretty much shuts down everything bar Skill Swap, which can be scouted by Protect. I don't have too much too say since Magic Bounce single-handedly blocks Stealth Rock, Spikes, and Taunt, while Mega Diancie is resistant to Knock Off and does not have an item that can be removed. Heal Bell can be used for other team support. Calm Mind threatens the opposing team more directly. Protect is probably ideal though, as it lets you Mega evolve for free, scouting for Skill Swap, so you can switch out the following turn and possibly even switch back to bounce back predicted hazards if you wish to do so. Moonblast is an easy 2HKO.

Calculations

252 SpA Mega Diancie Moonblast vs. 0 HP / 0 SpD Deoxys-S: 198-234 (82.1 - 97%) -- guaranteed 2HKO
4 Atk Deoxys-S Knock Off vs. 0 HP / 0 Def Mega Diancie: 21-25 (8.7 - 10.3%) -- possibly the worst move ever

 

[Polonium209]

So if you don't have a dedicated lead or a magic bouncer, this thing isn't too bad against Deo. The speedcreep and moveset are variable; the important thing is that it has 100+ Atk and Shadow Sneak.

Giratina-Origin @ Griseous Orb
Ability: Levitate
EVs: 128 HP/ 100 Atk / 248 Def / 32 Spe
Adamant Nature
-Shadow Sneak
-Dragon Tail
-Earthquake
-Defog

Giratina 2HKOes Deoxys-S with Shadow Sneak, which means that Deo gets maximum one layer of hazards up. If Deo doesn't taunt or switches out, you can easily defog any hazards away. You could also defog first turn if you think the opponent will set up rocks first. Being remarkably defensively fat, Giratina can also defog on many threats in the ubers tier if need be.
Unfortunately, if Deo has a Rocky Helmet instead of Focus Sash, then Giratina loses a lot of health, leaving it unable to stop certain threats.


This next one some people will think is a trash set, but it's pretty fun to use and 99% of the time screws over Deo so here it is.

Darkrai @ Choice Scarf
Ability: Bad Dreams
EVs: 4 HP / 252 Spa / 252 Spe
Timid Nature
-Dark Void
-Dark Pulse
-Trick
-(Filler: Nasty Plot, Ice Beam, etc)

Deo will most definitely Taunt, so you can blast it with Dark Pulse. Or switch items with it or whatever. With his incredible choice-scarf boosted speed, Darkrai can also help you check whatever friends came with Deo by outrunning them all, even at +1 or +2.