Project Victim of the Week

[Froggyboy]

Hard Check

Gourgeist-Super @ Leftovers
Ability: Frisk
EVs: 252 HP / 252 Def / 4 Atk
Impish Nature
- Will-O-Wisp
- Leech Seed
- Protect
- Seed Bomb

Ok, so this thing pretty much shows up a lot on here, so wynaut?
It is immune to CC and QA, while being able to take a Stone Edge just fine and 2HKOing with Seed Bomb or stall it out with Will-O-Wisp and Leech Seed. Though +2 Stone Edge sucks.
So basically, if it doesn't come in on an SD, Gourgist wins.

252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 252+ Def Gourgeist-Super: 133-157 (35.5 - 41.9%) -- guaranteed 3HKO after Stealth Rock and Leftovers recovery
0 Atk Gourgeist-Super Seed Bomb vs. 0 HP / 0 Def Terrakion: 188-224 (58.2 - 69.3%) -- guaranteed 2HKO
+2 252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 252+ Def Gourgeist-Super: 265-313 (70.8 - 83.6%) -- guaranteed 2HKO after Stealth Rock and Leftovers recovery

 

[The Bravest Bird]

reserving clefable

 

[The TurtleLord]

oh ok my apologies, must not have read it all

 

[Ruffles]

Tangrowth as a hard Check / ok counter

Tangrowth @ Leftovers
Ability: Regenerator
EVs: 248 HP / 252 Def / 8 SpD
Relaxed Nature
- Giga Drain
- Leech Seed
- Sleep Powder
- Knock Off

0 SpA Tangrowth Giga Drain vs. 0 HP / 0 SpD Terrakion: 192-228 (59.4 - 70.5%) -- guaranteed 2HKO
252 Atk Life Orb Terrakion Stone Edge vs. 248 HP / 252+ Def Tangrowth: 133-156 (33 - 38.7%) -- 99% chance to 3HKO after Stealth Rock and Leftovers recovery

252 Atk Life Orb Terrakion Close Combat vs. 248 HP / 252+ Def Tangrowth: 156-185 (38.7 - 45.9%) -- guaranteed 3HKO after Stealth Rock and Leftovers recovery
0 SpA Tangrowth Giga Drain vs. -1 0 HP / 0 SpD Terrakion: 288-342 (89.1 - 105.8%) -- 37.5% chance to OHKO

+2 252 Atk Life Orb Terrakion Close Combat vs. 248 HP / 252+ Def Tangrowth: 312-368 (77.4 - 91.3%) -- 25% chance to OHKO after Stealth Rock
0 SpA Tangrowth Giga Drain vs. -1 0 HP / 0 SpD Terrakion: 288-342 (89.1 - 105.8%) -- 37.5% chance to OHKO

Tangrowth wins 100% of the time unless Terrakion went for SD, and even then it has 37.5% chance to OHKO if Terrakion went to CC (most likely one) and with Giga Drain recovery and switching then switching back could possibly live one.

 

[Lil YoshiXD]

Reserving Wobufett

 

[firehusky]

I probably wouldn't use wobbuffet because there's always the 50/50 of terrakion going for either swords dance or stone edge...

 

[Salemance]

I probably wouldn't use wobbuffet because there's always the 50/50 of terrakion going for either swords dance or stone edge...

....but encore!

 

[firehusky]

Yeah that's why I said 50/50 because if wobbuffet tries to encore you into stone edge, then it'll probably lose, if it tries to counter you into swords dance, then it's even more riskier.

 

[Lil YoshiXD]

Yeah that's why I said 50/50 because if wobbuffet tries to encore you into stone edge, then it'll probably lose, if it tries to counter you into swords dance, then it's even more riskier.

God prediction in pokemon is so horrible. This game should have a best answer in every scenario that way we don't have to even think.

 

[The TurtleLord]

Celebi @ Leftovers
Ability: Natural Cure
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
- Giga Drain
- Psychic
- Thunder Wave
- Recover

Celebi as a check. if it comes in on close combat, then psychic will always ko after the sp def drop + 1 round of lo damage. Celebi also has thunder wave, which cripples terrakion for the rest of the game. Also, the chance of hitting a stone edge while paralysed is 0.6 i believe, so luck is definitely on your side. It takes very little from quick attack as well. The only bad scenario is when celebi comes in on Swords dance, as +2 stone edge along with +2 QA will ko celebi

Calcs:

Hide

252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 252+ Def Celebi: 153-181 (37.8 - 44.8%) -- guaranteed 3HKO after Stealth Rock and Leftovers recovery
4 SpA Celebi Psychic vs. 0 HP / 4 SpD Terrakion: 212-252 (65.6 - 78%) -- guaranteed 2HKO after Stealth Rock
4 SpA Celebi Giga Drain vs. 0 HP / 4 SpD Terrakion: 176-210 (54.4 - 65%) -- guaranteed 2HKO after Stealth Rock
4 SpA Celebi Psychic vs. -1 0 HP / 4 SpD Terrakion: 320-378 (99 - 117%) -- 93.8% chance to OHKO

 

[Inspirited]

Name: Latias

Check>counter

Latias @ Soul DewLife Orb
Ability: Levitate
EVs: 80 HP / 176 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Draco Meteor
- Psyshock
- Defog
- Roost

Latias is one of the better blanket checks offensive teams have for Terrakion, and, most importantly, its trainee Keldeo. If a safe switch cannot be secured, it is best to bring her in on a predicted Earthquake, Close Combat, or Quick Attack since Stone Edge + Quick Attack will KO always with Stealth Rock on the the field and has a chance to do so without. She will always outspeed Life Orb Terrakion though, and Psyshock will always OHKO Terrakion after a round of Life Orb recoil.

calcs

252 Atk Life Orb Terrakion Stone Edge vs. 80 HP / 0 Def Latias: 231-273 (71.9 - 85%) -- guaranteed 2HKO after Stealth Rock
252 Atk Life Orb Terrakion Quick Attack vs. 80 HP / 0 Def Latias: 62-74 (19.3 - 23%) -- 10.1% chance to 4HKO after Stealth Rock
252 Atk Life Orb Terrakion Close Combat vs. 80 HP / 0 Def Latias: 138-164 (42.9 - 51%) -- 97.7% chance to 2HKO after Stealth Rock
Terrakion Earthquake vs. Levitate Latias: 0-0 (0 - 0%) -- aim for the horn next time

176 SpA Life Orb Latias Psyshock vs. 0 HP / 0 Def Terrakion: 312-369 (96.5 - 114.2%) -- 75% chance to OHKO
176 SpA Life Orb Latias Draco Meteor vs. 0 HP / 0 SpD Terrakion: 253-298 (78.3 - 92.2%) -- guaranteed 2HKO

 

[The Bravest Bird]

Check

Clefable @ Leftovers
Ability: Unaware
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
- Moonblast
- Thunder Wave
- Moonlight
- Flamethrower

Clefable is completely unaware that terrakion is at +2. Thunder Wave slows down terrak and moonlight is for recovery since clef can't have soft-boiled and unaware on the same set. The rest is for a CM clef.

reserving clefable

 

[FullLifeGames]

Celebi @ Leftovers
Ability: Natural Cure
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
- Giga Drain
- Psychic
- Thunder Wave
- Recover

calcs:

Hide

252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 252+ Def Celebi: 153-181 (37.8 - 44.8%) -- guaranteed 3HKO after Stealth Rock and Leftovers recovery
4 SpA Celebi Psychic vs. 0 HP / 4 SpD Terrakion: 212-252 (65.6 - 78%) -- guaranteed 2HKO after Stealth Rock
4 SpA Celebi Giga Drain vs. 0 HP / 4 SpD Terrakion: 176-210 (54.4 - 65%) -- guaranteed 2HKO after Stealth Rock

Because you didn't mention if it's a check or a counter I will help you:
Celebi is a Check because it can't come in on a Swords Dance. If it does, Terrakion can then freely use Swords Dance again while Celebi can't kill Terrakion.
After +4 the Stone Edge calc makes it clear what will happen:
+4 252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 252+ Def Celebi: 456-538 (112.8 - 133.1%) -- guaranteed OHKO

Name: Latias

Check>counter

Latias @ Soul DewLife Orb
Ability: Levitate
EVs: 80 HP / 176 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Draco Meteor
- Psyshock
- Defog
- Roost

Latias is one of the better blanket checks offensive teams have for Terrakion, and, most importantly, its trainee Keldeo. If a safe switch cannot be secured, it is best to bring her in on a predicted Earthquake, Close Combat, or Quick Attack since Stone Edge + Quick Attack will KO always with Stealth Rock on the the field and has a chance to do so without. She will always outspeed Life Orb Terrakion though, and Psyshock will always OHKO Terrakion after a round of Life Orb recoil.

calcs

252 Atk Life Orb Terrakion Stone Edge vs. 80 HP / 0 Def Latias: 231-273 (71.9 - 85%) -- guaranteed 2HKO after Stealth Rock
252 Atk Life Orb Terrakion Quick Attack vs. 80 HP / 0 Def Latias: 62-74 (19.3 - 23%) -- 10.1% chance to 4HKO after Stealth Rock
252 Atk Life Orb Terrakion Close Combat vs. 80 HP / 0 Def Latias: 138-164 (42.9 - 51%) -- 97.7% chance to 2HKO after Stealth Rock
Terrakion Earthquake vs. Levitate Latias: 0-0 (0 - 0%) -- aim for the horn next time

176 SpA Life Orb Latias Psyshock vs. 0 HP / 0 Def Terrakion: 312-369 (96.5 - 114.2%) -- 75% chance to OHKO
176 SpA Life Orb Latias Draco Meteor vs. 0 HP / 0 SpD Terrakion: 253-298 (78.3 - 92.2%) -- guaranteed 2HKO

-------------------
Name: Weezing

Hide

Check > Counter

TANKWEEZING! (Weezing) @ Black Sludge
Ability: Levitate
EVs: 248 HP / 252 Def / 8 SpA
Bold Nature
IVs: 0 Atk
- Will-O-Wisp
- Sludge Bomb
- Pain Split
- Toxic Spikes

The idea with Weezing is to tank anything from Terrakion comfortably, burn it, Pain Spit off the damage, and then proceed to bring it down with burn, its own Life Orb, and Sludge Bomb. Weezing can also set Toxic Spikes after Terrakion is burned and Pain Split has been used which is a neat feature.

calcs

252 Atk Life Orb Terrakion Stone Edge vs. 248 HP / 252+ Def Weezing: 134-160 (40.1 - 47.9%) -- 3.9% chance to 2HKO after Stealth Rock and Black Sludge recovery
252 Atk Life Orb Terrakion Close Combat vs. 248 HP / 252+ Def Weezing: 81-95 (24.2 - 28.4%) -- 44.6% chance to 4HKO after Stealth Rock and Black Sludge recovery
252 Atk Life Orb Terrakion Quick Attack vs. 248 HP / 252+ Def Weezing: 36-44 (10.7 - 13.1%) -- possibly the worst move ever
Terrakion Earthquake vs. Levitate Weezing: 0-0 (0 - 0%) -- aim for the horn next time
252 Atk Life Orb burned Terrakion Stone Edge vs. 248 HP / 252+ Def Weezing: 66-79 (19.8 - 23.7%) -- possible 6HKO after Black Sludge recovery
252 Atk Life Orb burned Terrakion Close Combat vs. 248 HP / 252+ Def Weezing: 40-47 (12 - 14.1%) -- possibly the worst move ever
252 Atk Life Orb burned Terrakion Quick Attack vs. 248 HP / 252+ Def Weezing: 18-22 (5.4 - 6.6%) -- possibly the worst move ever

4 SpA Weezing Sludge Bomb vs. 0 HP / 0 SpD Terrakion: 46-55 (14.2 - 17%) -- 50.2% chance to 4HKO after burn damage

Sad to see that you already put so much work in this, but the rules are clear:
"5. From Saturday - Tuesday, each person can only nominate one Pokemon. From Wednesday to Friday/early Saturday, you can nominate as many as you want."

 

[Inspirited]

Sad to see that you already put so much work in this, but the rules are clear:
"5. From Saturday - Tuesday, each person can only nominate one Pokemon. From Wednesday to Friday/early Saturday, you can nominate as many as you want."

Alright. The last time I read the rules for here was when we were allowed one mon period, so I definitely jumped ship too quickly seeing previous weeks have 2 noms from some people. I ended up removing Weezing whom is now up for grabs.

Something strange is that your quote didn't give me an alert. ?_?

 

[FullLifeGames]

Something strange is that your quote didn't give me an alert. ?_?

This may be my fault, because I edited the quote in later.

 

[Clone]

reserving scarf landorus-t (different set, so its allowed)

Landorus-Therian @ Choice Scarf
Ability: Intimidate
EVs: 32 HP / 252 Atk / 224 Spe
Jolly Nature
- Earthquake
- Stone Edge
- U-Turn
- Knock Off / Superpower

This set is extremely standard. Scarf Lando can take any hit from Terrakion, classifying him as a check. he doesnt have to worry about Swords Dance unless Terrakion has previously boosted and Lando comes in on Stone Edge. So long as that doesnt happen, Lando can switch in up to three times if given just one free switch. Regardless, Landorus outspeeds and OHKOes with EQ, making him a great switch in and revenge killer to Terrakion.

 

[truedrew]

Posting 2 hard counters to SD LO Terrakion with quick attack
reserving Golurk for later posting doublade now

Doublade: Hard Counter
Item: Eviolite
Nature: Brave
Eve's: 252 hp 56 Attack 200 defense
-Gyro Ball
-Sacred Sword
-Rest
-Sleep Talk

Doublade is THE premier hard counter to this particular set as it is immune to Close combat and quick attack and it resists Stone edge by virtue of its amazing typing insuring that it fits the OP's definition of a counter "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." this is by far the most useful set as brave gyro ball always 1hko's terrakion regardless of the investment in attack by doublade, the investment is only there if on a sleep talk you pick up sacred sword it should be able to deal hefty chunks to terrakion as it is a guaranteed 2hko at the worst (without any hazards/LO recoil) And also the given investment allows doublade not to be a sitting duck vs other fast physical attacker (not the point). Rest Talk this gen is back as only 2 turns of sleep meaning that it is a very reliable form of recovery and allows doublade to switch into all the hazards the opponent can stack and still tank a +6 stone edge from terrakion (if the opponent can set up this much then you deserve to lose imo) and STILL FUCKING TANK THIS MOFO.

Calcs :+6 252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 200 Def Eviolite Doublade: 172-203 (53.4 - 63%) -- guaranteed 2HKO after Stealth Rock and 3 layers of Spikes

yeah dun matter

 

[FullLifeGames]

Posting 2 hard counters to SD LO Terrakion with quick attack
reserving Golurk for later posting doublade now

Doublade: Hard Counter
Item: Eviolite
Nature: Brave
Eve's: 252 hp 56 Attack 200 defense
-Gyro Ball
-Sacred Sword
-Rest
-Sleep Talk

Doublade is THE premier hard counter to this particular set as it is immune to Close combat and quick attack and it resists Stone edge by virtue of its amazing typing insuring that it fits the OP's definition of a counter "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." this is by far the most useful set as brave gyro ball always 1hko's terrakion regardless of the investment in attack by doublade, the investment is only there if on a sleep talk you pick up sacred sword it should be able to deal hefty chunks to terrakion as it is a guaranteed 2hko at the worst (without any hazards/LO recoil) And also the given investment allows doublade not to be a sitting duck vs other fast physical attacker (not the point). Rest Talk this gen is back as only 2 turns of sleep meaning that it is a very reliable form of recovery and allows doublade to switch into all the hazards the opponent can stack and still tank a +6 stone edge from terrakion (if the opponent can set up this much then you deserve to lose imo) and STILL FUCKING TANK THIS MOFO.

Calcs :+6 252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 200 Def Eviolite Doublade: 172-203 (53.4 - 63%) -- guaranteed 2HKO after Stealth Rock and 3 layers of Spikes

yeah dun matter

You can just reserve one Pokemon till Tuesday. Also Doublade and Golurk were already done:

Doublade as a Counter

Doublade @ Eviolite
Ability: No Guard
EVs: 252 HP / 4 Atk / 252 SpD
Sassy Nature
IVs: 0 Spe
- Rest
- Sleep Talk
- Gyro Ball
- Toxic

Basically the replacement for Aegislash, to handle Terrakion, Mega Gardevoir, etc. Doublade walls Terrakion by virtue of its typing, being immune to Close Combat and taking very little damage from a Life Orb Stone Edge, only fearing Earthquake which is not on the given set or very common. Even without any Defense investment, Doublade tanks all of Terrakions attacks and can KO with Gyro Ball, heal off damage with rest, or predict a switch out and cripple it with toxic.

Not super necessary, but here are calcs:

252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 0 Def Eviolite Doublade: 49-58 (15.2 - 18%) -- possible 6HKO

+2 252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 0 Def Eviolite Doublade: 99-117 (30.7 - 36.3%) -- 60.8% chance to 3HKO

0 Atk Doublade Gyro Ball (129 BP) vs. 0 HP / 0 Def Terrakion: 330-390 (102.1 - 120.7%) -- guaranteed OHKO

Terrakion Close Combat vs. Doublade: 0-0 (0 - 0%) -- aim for the horn next time huehue

Golurk@Leftovers
EV's: 252 Attack/164 Spe/92 HP
Trait: Iron Fist
Adamant Nature
-Stealth Rock
-EQ
-Fire Punch
-Ice Punch

The pokemon who made a name for itself in OU last gen for being such a good Terrakion counter is back again. Once again he resides in the lower tiers even with the buff to Ghost types this gen, but it doesn't mean he is any less effective against Terrakion now than last generation. Golurk is immune to both QA and Close Combat and resists Stone Edge, being 3HKO'd only about half the time after SR as long as Stone Edge doesn't miss. If Terrakion sets up an SD on the switch, it can only 2HKO Golurk, while EQ OKHO's back. The other moves gives Golurk some coverage and utility to hit things super effectively with Iron Fist boosted attacks and Stealth Rock beats up flying types that are immune to EQ. The EV's are a little weird aside from max attack, but they are to outspeed BD Azumarrill.

 

[Random Passerby]

Name : Latios
Status: Check

Latios @ Life Orb
Ability: Levitate
EVs: 252 SpA / 252 Spe / 4 SpD
Naive Nature

Moves:
- Draco Meteor
- Psyshock
- Earthquake
- Defog

Latios can come in on any of Terrakion's attack except Stone Edge, outspeed Terrakion and OHKO with a STAB Psyshock or Draco Meteor. Earthquake can be used to hit Heatran, Bisharp and Tyranitar hard on the switch-in. Defog is used to clear entry hazards.

Calculations:
252 Atk Life Orb Terrakion Stone Edge vs. 4 HP / 0 Def Latios: 255-302 (84.4 - 100%) -- 81.3% chance to OHKO after Stealth Rock
252 Atk Life Orb Terrakion Close Combat vs. 4 HP / 0 Def Latios: 152-179 (50.3 - 59.2%) -- guaranteed 2HKO after Stealth Rock
+2 252 Atk Life Orb Terrakion Quick Attack vs. 4 HP / 0 Def Latios: 136-161 (45 - 53.3%) -- guaranteed 2HKO after Stealth Rock
252 SpA Life Orb Latios Draco Meteor vs. 0 HP / 0 SpD Terrakion: 302-356 (93.4 - 110.2%) -- 93.8% chance to OHKO after Stealth Rock
252 SpA Life Orb Latios Psyshock vs. 0 HP / 0 Def Terrakion: 374-439 (115.7 - 135.9%) -- guaranteed OHKO

0 Atk Life Orb Latios Earthquake vs. 0 HP / 0 Def Heatran: 328-390 (101.5 - 120.7%) -- guaranteed OHKO
0 Atk Life Orb Latios Earthquake vs. 4 HP / 0 Def Bisharp: 172-203 (63.2 - 74.6%) -- guaranteed 2HKO after Stealth Rock
0 Atk Life Orb Latios Earthquake vs. 0 HP / 4 Def Tyranitar: 159-187 (46.6 - 54.8%) -- guaranteed 2HKO after Stealth Rock

 

[looiiyut]

Zygarde - Check

Zygarde @ Leftovers
Ability: Aura Break
EVs: 200 HP / 252 Def / 56 Spe
Impish Nature
- Glare
- Earthquake
- Dragon Tail
- Substitute

The most interesting mons are taken so I nominate Zygarde (parashuffler). Zygarde can come in all terrakion's moves. If terrakion uses CC on the switch is OhKOed by EQ. If Terra uses Stone edge or QA the best solution in my opinion is sub+glare.
The problem is SD on the switch (mind game): if terra goes for CC I can OhKO with EQ but if it uses another SW the best solution is sub+glare+EQ.
Set details: glare can also paralyze ground-type, EQ main stab, Dragon tail phazes out foes. Evs spread for max physical bulk, 56 Speed EVs are run to outspeed Bisharp.

0 Atk Zygarde Earthquake vs. 0 HP / 0 Def Terrakion: 236-278 (73 - 86%) -- guaranteed 2HKO

252 Atk Life Orb Terrakion Close Combat vs. 200 HP / 252+ Def Zygarde: 160-188 (39.3 - 46.1%) -- guaranteed 3HKO after Leftovers recovery
252 Atk Life Orb Terrakion Stone Edge vs. 200 HP / 252+ Def Zygarde: 66-78 (16.2 - 19.1%) -- possible 8HKO after Leftovers recovery
252 Atk Life Orb Terrakion Quick Attack vs. 200 HP / 252+ Def Zygarde: 36-43 (8.8 - 10.5%) -- possibly the worst move ever

 

[Random Passerby]

Since it is now Wednesday (in my country, at least) , reserving Gengar as a check.

 

[firehusky]

It's wednesday?
edit: where do you live

 

[FullLifeGames]

Check:

Venusaur @ Venusaurite
Ability: Chlorophyll
EVs: 252 HP / 240 Def / 16 Spe
Bold Nature
- Giga Drain
- Sludge Bomb
- Synthesis
- Hidden Power [Fire] / Leech Seed / Sleep Powder

Mega Venusaur can come in on every move Terrakion throws at it, except Swords Dance and win then every single time.

The problem with Terrakion going for SD is, that Mega Venusaur can't kill it and it can setup a second SD:
0 SpA Mega Venusaur Giga Drain vs. 0 HP / 4 SpD Terrakion: 210-248 (65 - 76.7%) -- guaranteed 2HKO
+4 252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 240+ Def Mega Venusaur: 398-469 (109.3 - 128.8%) -- guaranteed OHKO

Other than that:
252 Atk Life Orb Terrakion Stone Edge vs. 252 HP / 240+ Def Mega Venusaur: 133-157 (36.5 - 43.1%) -- guaranteed 3HKO
252 Atk Life Orb Terrakion Close Combat vs. 252 HP / 240+ Def Mega Venusaur: 79-94 (21.7 - 25.8%) -- 3.9% chance to 4HKO

 

[silver97]

check:

Azumarill @ Choice Band
Ability: Huge Power
EVs: 240 HP / 252 Atk / 16 Spe
Adamant Nature
- Waterfall
- Aqua Jet
- Play Rough
- Knock Off

can come in on every attack (even tho stone edge 2HKOs) and retaliate with an aqua jet that KOs if kion has taken some prior damage (this will likely happen since it has a LO). Assault vest is more common on azumarill and it checks kion as well, the only difference is that it has inferior power and it will be more difficult to kill with aqua jet, however it can cripple enough to allow teammates kill it easily or just let him die of LO recoil
252+ Atk Choice Band Huge Power Azumarill Aqua Jet vs. 0 HP / 0 Def Terrakion: 260-308 (80.4 - 95.3%) -- guaranteed 2HKO
252+ Atk Huge Power Azumarill Aqua Jet vs. 0 HP / 0 Def Terrakion: 174-206 (53.8 - 63.7%) -- guaranteed 2HKO

 

[Random Passerby]

Name : Gengar
Status: Check

Gengar @ Black Sludge
Ability: Levitate
EVs: 252 SpA / 252 Spe / 4 SpD
Timid Nature

Moves:
- Substitute
- Disable
- Shadow Ball
- Focus Blast

This is the classic Gengar Sub-Disable set. Notice that Gengar is immume to 3 of Terrakion's moves so your strategy is to get in, set up a Substitute and Disable the only move that threatens it. Alternatively, Gengar can choose to OHKO Terrakion with Focus Blast or click Shadow Ball to hit the switch-in hard. Substitute also has the utility of protecting Gengar from status, Pursuits and revenge killers while also enabling the user to pick a move safely.

Calculations:
252 Atk Life Orb Terrakion Close Combat vs. Gengar: 0-0 (0 - 0%) -- aim for the horn next time
252 Atk Life Orb Terrakion Stone Edge vs. 0 HP / 0 Def Gengar: 320-378 (122.6 - 144.8%) -- guaranteed OHKO
252 SpA Gengar Focus Blast vs. 0 HP / 0 SpD Terrakion: 286-338 (88.5 - 104.6%) -- 31.3% chance to OHKO