Cofagrigus @ Mental Herb
Ability: Mummy
Nature: Relaxed
IVs: 31/3/30/30/30/0
EVs: 252 HP, 40 Def, 216 SDef
-Shadow Ball
-Hidden Power [Fighting]
-Power Split
-Trick Room
Trick Room setter. Cofagrigus is chosen for its Ghost-typing, giving it immunity to Explosion.
Power Split is quite neat for neutralizing physical attackers if you have nothing better to do with Cofagrigus's 50 base Attack and a nearly perfect Attack IV. Cofagrigus's movepool is a bit barren, and crippling enemies before they move seems preferable to using Disable; though it only works on physical attackers. Note that it can also cripple Cofagrigus's Special Attack stat, howewer. In retrospect, this move is somewhat useless, but Cofagrigus's movepool is not very exciting for the Maison.
The EV spread allows Cofagrigus to survive Tyrantrum4 Strong Jaw Crunch, with the rest of the EVs dumped into SDef. It dies to Clawitzer4 Mega Launcher Dark Pulse.
Musharna @ Mental Herb
Ability: Telepathy
Nature: Relaxed
IVs: 31/1/31/30/30/0
EVs: 252 HP, 252 Def
-Psychic
-Hidden Power [Ground]
-Helping Hand
-Trick Room
Trick Room setter. Musharna is chosen for Telepathy, allowing it to survive Explosion and Earthquake to support the Weakness Policy Explosion gimmick.
Hidden Power Ground lets it activate Weakness Policy. Its usefulness for coverage is limited, but Musharna is often better off using Helping Hand anyway.
Relaxed with 252 Defense EVs allows it to survive Escavalier4 Megahorn. Clawitzer4 Mega Launcher Dark Pulse will OHKO it, howewer. Psychic typing is quite terrible defensively, and it is suspectible to Fake Out; it's definitely less reliable than Cofagrigus at setting up TR.
Sudowoodo @ Weakness Policy
Ability: Sturdy
Nature: Brave
EVs: 244 HP, 252 Atk, 4 SDef, 8 Spe
-Rock Slide
-Wood Hammer / Sucker Punch
-Explosion
-Protect
Weakness Policy Explosion with Sturdy.
Musharna and Cofagrigus, the two setters, carry HP Ground and HP Fighting respectively to hit Weakness Policy users super-effectively. After Weakness Policy Activates, they can use +2 Explosion to clear the field while the setter is immune to it. With Sturdy, the risk of Weakness Policy not working is low; you can also let the enemy activate Weakness Policy instead of hitting the user yourself. With Musharna, Helping Hand Explosion is also a safe, weaker option if there's a risk.
Wood Hammer and Sucker Punch are the options for the second move. Hitting Waters seems more useful as the teams often end up being weak to Water, so I use Wood Hammer.
The Speed EVs let it outspeed Cofagrigus by one point so HP Fighting moves before it.
Sudowoodo's niche in this position is its very low Speed (30) and unique movepool. Gigalith would have better stats all around, but outside Rock Slide its movepool is nonexistent and the extra stats "aren't needed" when mostly using +2 Explosion. Gigalith would also need to be bred in White due to it requiring a weird Speed IV to hit 31 Speed, where acquiring its egg moves would be a pain.
Kecleon @ Expert Belt
Ability: Protean
Nature: Brave
EVs: 252 HP, 252 Atk, 4 Def
-Fake Out
-Shadow Sneak
-Drain Punch
-Fire Punch
Side position. The last two moves can be changed depending on what coverage is desired; Thunder Punch does decently to alleviate a Water-type weakness, for example.
Dragalge @ Choice Specs
Ability: Adaptability
Nature: Quiet
EVs: 252 HP, 4 Def, 252 SAtk
-Dragon Pulse
-Sludge Bomb
-Thunderbolt
-Scald
Adaptability Dragon Pulse hits very hard across the field. Choice Specs boosts it further, making it around as powerful as Life Orb Latias Draco Meteor.
Thunderbolt and Scald are filler. HP Fire or HP Ground could be better, but locking into either would be a bad idea and Dragon Pulse hits really hard, so they would seldom be needed.
Abomasnow @ Abomasite / Focus Sash
Ability: Snow Warning
Nature: Quiet
EVs: 252 HP, 252 SAtk, 4 SDef
-Blizzard
-Grass Knot
-Shadow Ball
-Protect
Center. If the Mega Stone is taken, give it Sash; Blizzard is quite nice and if you have Abomasnow on the team, you can slash Ice Beam for Blizzard where applicable. (It never is with this pool, but maybe in the future...)
Eelektross @ Life Orb / Expert Belt / Choice Specs
Ability: Levitate
Nature: Quiet
EVs: 252 HP, 4 Def, 252 SAtk
-Thunderbolt
-Grass Knot
-Flamethrower
-Hidden Power [Ice] / Protect
I'm not really sold on this Pokémon. STAB Thunderbolt isn't bad, but it seems very mediocre and nondescript - which also makes it effective at these random teams. It doesn't synergize in a great way with anything with its decent at best stats and lack of strengths, but it doesn't really introduce any gaping weaknesses into the line-up either. As a result I consider it mostly trash for serious teams with little value to it, but very decent filler that can be put in any position for randomly generated Trick Room teams.
Golem @ Weakness Policy
Ability: Sturdy
Nature: Brave
EVs: 252 HP, 252 Atk, 4 Def
-Earthquake / Rock Slide
-Sucker Punch
-Explosion
-Protect
Weakness Policy Explosion with Sturdy. Earthquake vs Rock Slide depends on lead partners; Earthquake is preferred with Musharna as the TR setter and an EQ-immune ally.
Earthquake + Rock Slide could also be an option, but since Sucker Punch is a 4th gen tutor that I don't want to get rid of, I'd have to breed a new Golem for it.
Steelix @ Weakness Policy
Ability: Sturdy
Nature: Brave
IVs: 2 Speed
EVs: 252 HP, 252 Atk, 4 SDef
-Gyro Ball
-Earthquake
-Explosion
-Protect
Weakness Policy Explosion with Sturdy. The Speed IV gives it 31 Speed, outspeeding Cofagrigus by one point.
Steelix is surprisingly powerful. Its bulk and typing often let it use Weakness Policy without friendly fire, and spamming Earthquake is very effective when viable and can sweep teams on its own - especially with both Weakness Policy active and a Helping Hand boost on top.
Ferrothorn @ Iron Ball
Ability: Iron Barbs
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Gyro Ball
-Seed Bomb
-Explosion
-Protect
I wanted a boosting item over Rocky Helmet or a berry. Iron Ball is picked to increase Iron Ball's base power to 150 against anything with 66 or more Speed. Since Gyro Ball is its main move, it seemed like a good option.
Explosion as the third move to go out with a bang when the situation calls for it. It isn't the strongest Explosion, but it beats wasting turns when it can't harm the opponents.
Conkeldurr @ Assault Vest
Ability: Iron Fist
Nature: Brave
EVs: 108 HP, 252 Atk, 4 Def, 144 SDef
-Drain Punch
-Knock Off
-Ice Punch
-Mach Punch
EV spread lifted from Eppie's Conkeldurr. Conkeldurr is amazingly powerful, and I can see why it is used in the top Doubles team.
Torkoal @ Choice Specs
Ability: Shell Armor
Nature: Quiet
EVs: 252 HP, 252 SAtk, 4 SDef
-Eruption
-Earth Power
-Flamethrower
-Protect
With Specs boosting its Special Attack to 225, Torkoal's Eruption is slightly stronger Mega Camerupt's Eruption while being equally slow at 20 base Speed. The other moves are never used.
Gyarados @ Power Item
Ability: Intimidate
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Waterfall
-Return
-Rain Dance
-Protect
Rain Dance in the third slot to support Water Spout users, which I don't have any of yet. Its movepool is quite barren, so there's not much to put in this slot.
Volcarona @ Power Item
Ability: Flame Body
Nature: Quiet
EVs: 252 HP, 4 Def, 252 SAtk
-Fiery Dance
-Bug Buzz
-Giga Drain
-Protect
Same as ReptoAbysmal's Volcarona, except with Protect to use it as a lead and capitalize on its weaknesses over Hurricane. Credit to him for coming up with the idea to give a Power item to Volcarona of all things; it sounds so bad, but in practice it is much stronger than you'd expect.
Better than expected for something as seemingly weak as Volcarona isn't that much, though - if it gets a boost from Fiery Dance, it can perform, but it's very unreliable and bottom-of-the-barrel if you don't get a boost in 1-2 attacks.
Arcanine @ Power Item
Ability: Intimidate
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Flare Blitz
-Close Combat
-Crunch
-Protect
I'm not really sure where I want to go with this thing just yet, or if I even want to keep it in the pool - it seems like a pretty bad power item user.
Staraptor @ Power Item
Ability: Reckless / Intimidate
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Brave Bird
-Double-Edge
-Close Combat
-Protect
Cross-field Brave Bird is very strong. Staraptor is picked over Talonflame since it can actually use its coverage moves under Trick Room while holding a Power item, while Talonflame is just too fast to get away with Flare Blitz. Reckless increases damage output, and is generally preferred; I have one with Intimidate, but never picked it over Reckless.
This is the strongest Power Item user in the pool of the ones I have so far. Brave Bird is just a great move to spam, even with something as un-TR-like as Staraptor.
Azumarill @ Assault Vest
Ability: Huge Power
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Play Rough
-Waterfall
-Aqua Jet
-Superpower
Assault Vest chosen for longevity. "Don't use Play Rough."
Salamence @ Power Item
Ability: Intimidate
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Dragon Claw
-Earthquake
-Flamethrower
-Protect
Intimidate. Aside from Dragon Claw and Earthquake, its accurate movepool is quite barren, so I went mixed without investment. This is not terribly effective, and I might just scrap it altogether and use Dragonite instead.
Tyranitar @ Focus Sash
Ability: Sand Stream
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Crunch
-Rock Slide
-Low Kick
-Protect
Focus Sash lets it survive an attack, and will almost always stay intact thanks to Sand Stream. Low Kick is preferred over Superpower to avoid Attack drops so it doesn't have to switch out prematurely.
Scrafty @ Assault Vest / Sitrus Berry
Ability: Intimidate
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Drain Punch
-Knock Off
-Ice Punch
-Fake Out
Standard Scrafty. Focusing on survivability with Assault Vest / Sitrus seems good, but I'm not entirely sure.
Machamp @ Assault Vest / Life Orb / Expert Belt
Ability: No Guard
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Dynamic Punch
-Knock Off
-Ice Punch
-Stone Edge
Machamp is decent with Assault Vest, but Conkeldurr and Scrafty generally make better use of it. If it can't get the vest, it uses a boosting item decently.
Clawitzer @ Life Orb
Ability: Mega Launcher
Nature: Quiet
EVs: 252 HP, 252 SAtk, 4 SDef
-Aura Sphere
-Dark Pulse
-Water Pulse
-Ice Beam
Aura Sphere is a great attack, and Clawitzer is very strong - its main flaw is its rather high base 59 Speed. It's pretty much the "Mega Lucario of Trick Room".
Reuniclus @ Life Orb
Ability: Magic Guard
Nature: Quiet
EVs: 252 HP, 252 SAtk, 4 Def
-Psychic
-Energy Ball
-Shadow Ball
-Helping Hand
Reuniclus seems to suck for the most part. STAB Psychic is a powerful attack, but other than that it contributes very little. If it loses out on Life Orb due to item conflicts, it goes from mediocre to worse with a Regenerator Assault Vest sideboard that does very little.
Mawile @ Mawilite
Ability: Intimidate
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Iron Head
-Play Rough
-Sucker Punch
-Protect
Play Rough's inaccuracy hurts a lot, and Iron Head isn't half as good. It uses the Mega slot decently, but I'd rather have a Weakness Policy Explosion user or even Torkoal as a back-up to sweep faster.
Rolling this Pokémon causes a lot of item conflicts, as unlike all other Megas in the pool, Mawile's Mega Stone is non-negotiable. If I add any more Megas to the pool, it will probably be necessary to add a Mega slot or at least a restriction for problematic Megas like Mawile and Ampharos to avoid the most disastrous conflicts.
Camerupt @ Cameruptite / Choice Specs
Ability: Solid Rock
Nature: Quiet
EVs: 252 HP, 252 SAtk, 4 SDef
-Eruption
-Earth Power
-Flamethrower
-Protect
Eruption is a good move. If the Mega slot is taken, Specs Camerupt can be run as a faster, harder-hitting Specs Torkoal in the back.
Slowbro @ Slowbronite
Ability: Own Tempo
Nature: Sassy
EVs: 252 HP, 4 SAtk, 252 SDef
-Scald
-Iron Defense
-Calm Mind
-Rest
Mega Slowbro come in after an ally is KO'd and Trick Room is active into a side position; from there, it can begin boosting with the Speed advantage and hopefully reach enough boosts to become invincible before Trick Room runs out while allies create space. If succesful, it has the potential to sweep 1v6 barring OHKO moves. Rest over Slack Off to avoid losing to Toxic.
Crawdaunt @ Choice Band
Ability: Adaptability
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-Knock Off
-Waterfall
-Superpower
-Aqua Jet
Choiced back-up. Hits hard, but is a bit fast and not that great it locks into something other than Knock Off.
Rhydon @ Eviolite
Ability: Lightning Rod
Nature: Brave
EVs: 100 HP, 156 Atk, 252 SDef
-Drill Run
-Rock Slide
-Earthquake
-Protect
Rhydon is used over Rhyperior for Lightning Rod. Drill Run is accurate-ish and doesn't hit allies, and Megahorn isn't really missed. Having both Drill Run and EQ lets it always use a Ground STAB.
I intended to EV it with a spread of 108/156/0/0/244/0, but forgot about that when EV training and it ended up a bit off. I lifted the idea of cutting its Attack from a VGC report on Nugget Bridge and the intended spread is identical to that one (it simply drops Attack by 10 points, hitting a 185->187 Nature boost point) but for slightly different reasons: Rock Slide and Drill Run are both inaccurate and not that powerful, so prioritizing bulk and the ability to spam them for as long as possible over maximizing their (unimpressive) power could be worth it. I also wanted to differentiate it from Rhyperior (to be added to the pool), which has higher Attack and will likely maximize it and can utilize a boosting item or Wide Lens to take advantage of it.
Aegislash @ Life Orb / Leftovers
Ability: Stance Change
Nature: Brave
EVs: 252 HP, 252 Atk, 4 SDef
-King's Shield
-Iron Head
-Sacred Sword
-Shadow Sneak
I'm not convinced this is the way to go for Aegislash in a Trick Room team, but I had one so I threw it on.