B101 ORAS OU Tutoring Guide
***KEEP IN MIND THAT A LOT OF POKEMON IS ARBITRARY***
***THEREFORE, THERE IS A LOT OF VARIABILITY WITH SOME OF THESE DEFINITIONS DEPENDING ON WHO YOU ASK***

Three Main Playstyles + Blended/In-Between Playstyles:
Hyper Offense / Bulky Offense / Balance / Semi-Stall / Stall

General Notes that relate to all playstyles:
SR is the lynchpin of the tier. Use it.
Hazard Removal is always helpful, but some mons are more affected by hazards than others. Be aware of this when deciding if removal necessary for your team. (HINT: it probably is.)
Some mons in the tier are common enough threats to all teams that I find it necessary to make sure I have these mons dealt with accordingly. These mons in no particular order: Latios/Latias, Keldeo, Lando-T/Garchomp, Clefable, Heatran, Bisharp, Tyranitar/Excadrill
Some attacking types are more effective than others, and because of this, I find it helpful to pack the following resists/immunities. The list is pretty arbitrary, but I have found it helpful to create teams with good type-synergy.
2 Water Resists
2 Dragon Resists
2 Psychic Resists or 1 Immunity
2 Ground Resists or Immunities - At least 1 not bypassed by Mold Breaker
1 Fighting Resist
1 Fire Resist
1 Bolt/Beam Resist or Neutrality
1-2 Flying Resists
1 Dark Resist/Knock Off Absorber

Now, on to specific playstyles.

Hyper Offense
Relies on exerting offensive pressure to overwhelm opposing teams.
Forced to be content with checking threats, rather than countering them.

General Build:
Sweeper / Sweeper / Breaker / Cleaner / Stealth Rock Setter / Filler

Sweepers carry a set-up move, and try to sweep opposing teams after using that move.
ORAS OU has lots of different sweepers. They can be special or physical threats, though physical set-up sweepers are more common. Your sweepers should complement each other for the most part - A beats B's checks and vice versa.
Examples of Physical Sweepers: DD CharX, BD Azumarill, SD Bisharp, Double Dance Lando-T, PuP M-Lop
Examples of Special Sweepers: TG Manaphy, CM Keldeo, Nasty Plot Thundurus, Contrary Serperior, QD Volcarona
Examples of Mixed Sweepers: RP M-Diancie, Mixed DD M-Alt

Breakers are able to do a lot of damage without the need to set up. ORAS OU again has lots of variable breakers, but there is a pattern in terms of items. That is, breakers often carry Choice Specs/Band, LO, or a Mega-Stone.
Examples of Breakers: CB Azumarill, LO Hoopa-U, Specs Keldeo, LO Latios, LO Thundurus, LO Weavile, M-CharY, M-Gardevoir, M-Medicham

Cleaners do just that, clean opposing teams once they are weakened. The most important factor in a cleaner is speed, so fast Megas, scarfers, and mons with priority fit the bill nicely. The term "revenge killer" is nearly synonymous with cleaner.
Examples of Cleaners: M-Alakazam, M-Manectric, Scarf Keldeo, Talonflame, CB Dragonite

Stealth Rock has been a keystone of pokemon since its inception, so naturally it is required on pretty much any competitive team. For HO, the SR setter will oftentimes be the dedicated lead, though some other types of setters have found their way onto offensive teams. By this, I refer to TankChomp primarily, as it first found its niche on offensive teams as a means of checking mons that HO normally struggles with (Bisharp, M-Lop, etc.),
Examples of SR Setters: Azelf, Focus Sash Lando-T, TankChomp, SD Lum Garchomp

The filler slot is used to cover whatever weaknesses your team may have. The slot is often best served by a pivot (Rotom-W, Torn-T) or a Prankster Twave user (Klefki, Thundurus). Pivots help to keep momentum on your side while Prankster Twave users help to check opposing set up sweepers (CharX) who could otherwise demolish offensive teams after a single set up move.

So, that is the basic build for HO teams, but it is important to remember that it is meant to be extremely general. Half of building in pokemon is role compression, so do not allow this basic skeleton to limit your ideas or building.

Bulky Offense
Typically follows the build of offensive teams, so it can be difficult and somewhat arbitrary to categorize teams accordingly. However, there a couple distinctions that can make things clearer.
1. Pure HO or Offensive teams rarely carry healing moves. As such, you are more likely to find bulky sweepers on bulky offense. (Think 3 attacks DD M-Alt vs Defensive DD M-Alt or CM Keldeo vs CM Clefable).
2. Bulky Offense teams tend to be slower and bulkier. I know this is obvious, however, the bulk aspect can be quanitized via that 80/80/80 rule. That is, a good candidate for bulky offense should have defensive stats of around 80/80/80 or higher.

Balance
Contains both defensive and offensive mons on the same team. Generally works toward wearing down teams with the defensive core and breaking/sweeping at the appropriate times with the offensive mons.
A couple distinctions from offense:
1. You actually want to try to counter as much of the metagame as possible. If not packing a counter to a specfic threat, you will usually be able to pack at least a couple checks.
2. The importance of hazards is amplified for balance teams. This is because defensive mons oftentimes need hazards off the field in order to counter mons appropriately. As such, hazards removal is practically mandatory for balance teams, and as always, you absolutely want a SR user at the very least.

So the general build for balance is as follows; however, be aware that balance offers a large degree of freedom when building, so these roles are not explicitly required.
Physical Sweeper/Breaker / Special Sweeper/Breaker / Physical Wall / Special Wall / Breaker / Filler

The Sweeper, and Breaker roles are very similar to roles found on Offense. Cleaners can also fulfill these roles, keeping with the large degree of freedom balance offers. Generally, certain combinations of these roles are more effective than others. As such, I find that Sweeper / Sweeper / Breaker or Sweeper / Cleaner / Breaker or Sweeper / Breaker / Breaker are the most efficient.

The final three slots (Physical Wall / Special Wall / Filler) usually make up a defensive core. Again, there is a lot of freedom here, so don't feel it necessary to have a dedicated special wall or dedicated physical wall. Instead, focus on putting together a core with good synergy.

For beginners, types cores are an easy and sort of fun way to get into making cores. These cores rely on type synergy - resisting each others weaknesses - to be effective. It works fairly well in practice, and is a good way to start off building cores. Prevelant and effective type cores are Fire / Water / Grass and Fairy / Dragon / Steel. Water / Ground is also a rather effective two-mon type core with a Grass or Steel type in the third slot.

FWG Cores
This dates back to RB starters, but it still works.

An example core:
Fire - Heatran / Water - Starmie / Grass - M-Venusaur

Tran is weak to                          Water, Fighting, Ground
Starmie is weak to                     Bug, Electric, Ghost, Grass, Dark
M-Venusaur is weak to               Flying, Psychic + Ice, Fire (Pre-mega)

Bolded types are resisted by both partners, italics are resisted by one.
Clearly, this core covers each other's weaknesses from a typing perspective rather well. However, consider how else these mons may support each other. Starmie provides Rapid Spin support, which the other two appreciate. There are other advantages this core brings, which brings us to how to build a "more advanced core".

With this core, you want to start with a single mon. With this mon in mind, make a list of mons that trouble it. Choose a second mon that covers as many of this mon's weaknesses as possible. Then, make a list of mons that mon 2 is weak to, and repeat the process to choose a third mon. I then recommend making a list of mon 3's weaknesses as well. Then, go through your three lists and cross off things that are checked by other mons in your core. Try to remedy any obvious weaknesses via coverage moves or by making sure your offensive threats beat them.

An example:
Start with: Hippowdon
Weak to: Clefable, Manaphy, M-Sableye, M-Alakazam, Azumarill, Keldeo, Lando-T, Latios, M-Scizor, Weavile, M-CharY, M-Gardevoir, Gengar, Gliscor, M-Gyarados, Kyurem-B, Serperior, Slowbro, M-Venusaur, Alakazam, Breloom, Rotom-W, Starmie
2nd Mon: AV Tornadus-T
Weak to: M-CharX, Clefable, Manaphy, M-Altaria, Azumarill, M-Diancie, M-Lopunny, M-Metagross, Talonflame, Thundurus, Weavile, M-CharY, Kyurem-B, M-Manectric, Tyranitar, Raikou, Rotom-W
3rd Mon: Ferrothorn
Weak to: M-CharX, M-Alakazam, Heatran, Keldeo, Talonflame, Tornadus-T, M-CharY, M-Manectric, M-Medicham, Serperior, Magnezone, Volcarona

As you can see, most of each of the lists is crossed off. This lets me know that I have a fairly effective core in the works. Anything not crossed off should be taken care of with your offensive mons or by trying to lure it in somehow and surprise it with one of your defensive mons.

This process can be very tedious, so it is perfectly fine to do it in your head. However, I have found that writing things out can be very helpful for beginning team builders.

Semi-Stall
To me, Semi-Stall is sort of just a catch all for teams that aren't full stall, but may have a few stall mons. Focus on hazards is again amplified. Tend to have a couple utility or offensive mons that fill important roles. (i.e. Scarf Tyranitar to trap hazard removers)

Stall
Stall as a general playstyle tries to outlast opposing teams. There aren't really specific roles on stall teams because its about trying to wall as much of the metagame. Therefore, it is more apt to discuss specific mons on stall. I have divided them by viability.

High Viability - These mons are very important to stall.

Mega-Sableye: The premiere stall mega of ORAS. Its existence is enough for me not to classify any other megas as high viability. It is that useful. The control it provides over the hazard game is hugely important for stall teams. It also has decent stats, good typing, and an excellent movepool (Recover, Will-O-Wisp, Calm Mind, Knock Off, Foul Play, etc.).

Chansey: Number one pink blob. It walls just about half of the meta with Eviolite in tact. Generally serves as a cleric w/ Heal Bell, but also has access to other utility moves such as Stealth Rock, Thunder Wave, and Toxic. Seismic Toss is only source of damage, and Soft Boiled is its most reliable form of healing.

Skarmory: Physically Defensive variants are more common on stall, but SpDef variants also see some degree of usage. Typically carries Defog, as it is the best hazard remover full stall has to offer. Also carries Roost for healing. Last two moveslots are usually an atacking move (Iron Head, Bravd Bird, and Counter on Phys Def variants), and another status move (Taunt, Toxic, Spikes).

Quagsire: Unaware Def Quag is an amazing check to loads of physical attackers and set up sweepers, as well as most electrics by virtue of its typing. Recover, Scald, Toxic, Earthquake is the standard moveset and there is little need for variation most of the time.

Amoonguss: A very valuable mixed wall that functions well as a pivot due to its ability, Regenerator. Also provides an important fairy check to stall, as many fairy types threaten stall heavily. It has a useful support movepool - Spore, Stun Spore, Clear Smog, as well as a decent offensive movepool - Giga Drain, Sludge Bomb, HP Ice/Fire, even Foul Play

Clefable: Unaware Clefable checks a number of threats - perhaps TG Manaphy most notably, but much like Quagsire, it checks a wide array of threats. WishTect + Moonblast + Heal Bell is the standard Unaware cleric set, though some other moves can be used occasionally, MG Clef is another useful mon on stall because it can check so much, but it is less common.

Slowbro: Impressive physical bulk and great defensive typing are what Slowbro brings to Stall. It also has a vast movepool to make use of offensively and defensively. Scald, Psyshock, Slack Off, Thunder Wave, Toxic, Calm Mind are all common choices. Regenator is also immensely helpful, as one would expect.

Medium Viability - These mons are somewhat important to stall

Mega-Charizard X

Heatran

Mega-Scizor

Talonflame

Mega-Slowbro

Mega-Latias

Mandibuzz

Suicine

Alomomola

Cresselia

Reuniclus

Gastrodon

Mew

Mega-Venusaur

Slowking

Low Viability - These mons can be found on stall teams, but there are usually better options.

Mega-Altaria

Hippowdon

Mega-Aggron

Blissey

Jellicent

Shedinja

Sableye

Chesnaught

Azumarill