Out of the many additional Pokemon that roam free in CAP, it's no stretch to say that Colossoil is a creation that has had one of the most significant impacts on the metagame as a whole. For starters, Colossoil's capabilities as a spinner are nearly unmatched; it's one of only two Dark-type users of Rapid Spin (the other being Malaconda) and has a powerful STAB Knock Off coming off of an impressive base 122 Attack, which is enough to heavily deter nearly any Ghost-type from trying to spinblock it. Colossoil is notable for much more than just Rapid Spin, though; it has several other powerful STAB options such as Earthquake, Sucker Punch, and Pursuit, broadening its capabilities as an offensive Pokemon. Having access to U-turn is also incredibly helpful for more offensively oriented teams, as it allows Colossoil to act as a much more effective pivot and preserve momentum for its team. Colossoil also has access to two useful abilities, including its signature ability, Rebound, which can bounce back status moves, entry hazards, and basketballs on the turn it switches in, and Guts, which makes it a threatening status absorber. Finally, Colossoil's unique stat spread makes running either defensive spreads or offensive spreads both feasible and viable. All of these defining traits make it a versatile and useful addition to numerous team archetypes.
As influential and threatening as Colossoil is, it still has some fairly notable flaws that can be exploited. For instance, although Colossoil's Dark / Ground typing gives it four resistances and two immunities, it's also plagued with six weaknesses, many of which are prevalent attacking types in the metagame. Having weaknesses to the common Fairy-, Water-, and Fighting-type attacks is never a great attribute to have, hampering Colossoil's ability to pivot and support the team. Offensively, Colossoil's typing can leave it struggling to do much of anything against some prominent physical walls, the most notable of which is Tomohawk, which hard walls Colossoil with ease thanks to its typing and access to Prankster Roost. Furthermore, Colossoil's STAB combination often isn't enough to prevent opposing setup sweepers such as Mega Altaria and Mega Scizor from using it as easy setup fodder, which can prove detrimental to Colossoil and its teammates. In spite of Colossoil's shortcomings, its numerous strengths and versatility have secured its niche as one of the best spinners CAP has to offer, a potent offensive pivot, and a surprisingly talented basketball player.
The first two moveslots are just about mandatory for any of Colossoil's sets to ensure that it can fully take advantage of its high Attack and potent STAB combination. Earthquake is Colossoil's strongest and most reliable STAB move, hitting any foe that isn't resistant or immune to the move for solid damage. Knock Off is also quite strong with the STAB boost, hitting Ghost- and Psychic-types for high damage, and it is also useful for its ability to remove the foe's item.
There's more room for variety in Colossoil's third and fourth moveslots, however, as the choice of moves highly depends on which type of role Colossoil is required to play on its team. Rapid Spin allows Colossoil to clear entry hazards, and it's an excellent user of the move thanks to its Dark-type STAB moves deterring Ghost-types from attempting to spinblock it. Sucker Punch gives Colossoil strong priority and a method of checking faster threats. U-turn allows Colossoil to pivot out of its checks and counters as they switch into it, allowing one of Colossoil's teammates to switch in safely. Pursuit is used to trap and KO Psychic- and Ghost-types, such as Latios, Latias, Gengar, and Kitsunoh, that could otherwise escape from Colossoil by switching out.
Maximum Attack investment and an Adamant nature are used to let Colossoil hit hard with its STAB moves. Most of the remaining EV investment goes towards bolstering Colossoil's special bulk, which, when combined with Assault Vest, allows it to easily sponge special hits and support its team. The 36 EVs in Defense are used to avoid the OHKO from Life Orb Syclant's Superpower after Stealth Rock damage.
The ability choice is largely dependent on the team Colossoil is on. Guts provides Colossoil with a hefty boost to its Attack if it is crippled with status, allowing it to act as a potent status absorber for its team, and is often the superior choice for more balanced or bulky offensive teams. Rebound, however, can be used to bounce back status moves and entry hazards on the turn Colossoil switches in, which is often more useful for faster-paced teams that appreciate the ability to more aggressively pressure opposing status inducers and entry hazard setters. Rebound is also a good option if Colossoil isn't running Rapid Spin, as it retains some of its potential for controlling entry hazards with this ability.
Colossoil should come in on Pokemon it forces out, such as Cyclohm and Mega Manectric, so that it can easily pressure the foe and perform its duties for the team, be it through Knock Off, Rapid Spin, or simply grabbing momentum with U-turn. If using Guts, switching in on a potential status user allows Colossoil to gain an Attack boost from the move, putting even more power behind its attacks. If using Rebound, switch in on potential entry hazard setters and status users, as this turns the foe's moves against them. Don't switch in on Leech Seed users, however, as the Grass-type users of the move are immune to it themselves and threaten Colossoil with their Grass-type STAB attacks. Rebound can also be used to bounce back Roar and Whirlwind, which can potentially bring in a Pokemon that Colossoil has a favorable matchup against, such as a Ghost- or Psychic-type, which Colossoil can then remove from the game with Pursuit. Use Sucker Punch to revenge kill weakened faster threats. Beware of faster priority users such as Syclant, Talonflame, and Cawmodore, however, as well as potential Substitute users. Also, be cautious around Pokemon such as Necturna and Aurumoth, as they occasionally run Colbur Berry to weaken Colossoil's Dark-type STAB moves and can hit Colossoil hard with their own STAB attacks.
Flying-types such as Talonflame, Cawmodore, and Tomohawk pair well with Colossoil, as they love the Rapid Spin support that it provides, and in return, they can easily dispatch of the Grass- and Fighting-types that threaten Colossoil. Fairy-types such as Mega Altaria, Mega Gardevoir, and Sylveon can easily handle Fighting-types, namely Tomohawk, for it, while Colossoil can beat Fire-, Poison-, and Steel-types for them in return. Steel-types such as Mega Scizor, Skarmory, and Heatran can handle opposing Fairy-types for Colossoil. Wish support from the likes of Chansey, Clefable, and Sylveon is useful to keep Colossoil healthy, as it has no reliable recovery and could otherwise be easily worn down over time.
Earthquake is a powerful STAB move and hits impressively hard thanks to the boosts from STAB and Life Orb, allowing it to heavily dent any foe that isn't resistant or immune to the move. Knock Off gives Colossoil a powerful method of dealing with opposing Ghost- and Psychic-types, removes the foe's item, and can benefit from either Life Orb or Black Glasses. U-turn is necessary to allow Colossoil to pivot out of foes it can't heavily damage, such as Tomohawk and Mega Altaria, allowing a teammate better equipped to handle the situation to switch in. Sucker Punch provides Colossoil with priority, allowing it to act as a revenge killer for faster Pokemon. Pursuit hits Psychic- and Ghost-types hard if they try to switch out of Colossoil, such as Latios, Latias, Gengar, and Kitsunoh.
252 EVs in Attack and Speed are used to maximize Colossoil's offensive potential. A Jolly nature lets Colossoil make the best use of its base 95 Speed, ensuring that it outspeeds all non-Choice Scarf variants of Aurumoth. An Adamant nature can be used to let Colossoil hit even harder and still have enough Speed to outpace Jolly Necturna. Life Orb gives Colossoil a significant increase to its damage output but can leave it prone to being worn down rather quickly; Black Glasses can be used instead if Colossoil's longevity is of high importance, as it still provides a decent boost to Knock Off as well as its other Dark-type attacks. Guts allows Colossoil to function as a status absorber, providing it with an Attack boost should it become inflicted with a status ailment. Rebound, on the other hand, can be used to completely deflect status moves as well as entry hazards, but it only works on the turn Colossoil switches in.
Colossoil can be utilized as an all-out attacker with its powerful STAB moves, provide Knock Off support for the team, or simply act as a pivot with U-turn. If using Guts, try to switch in on potential Will-O-Wisp or Toxic users to give Colossoil a large boost to its Attack. If using Rebound, Colossoil can freely switch in on many status, Stealth Rock, and Spikes users and bounce the moves back at the foe. Sucker Punch should be used to revenge kill faster Pokemon; just beware of faster priority users such as Syclant, Talonflame, and Cawmodore. Be cautious around potential Colbur Berry users as well, notably Necturna and Aurumoth, as they can easily survive a hit from Colossoil and retaliate with their STAB moves.
Flying-types such as Talonflame, Cawmodore, and Tomohawk can easily deal with Grass- and Fighting-types for Colossoil. Offensive Fairy-types such as Mega Altaria, Mega Gardevoir, and Sylveon can easily handle Fighting-types for it, while Colossoil can take care of Fire-, Poison-, and Steel-types in return. Steel-types such as Mega Metagross, Heatran, Kitsunoh, Mega Scizor, and Skarmory can all take on opposing Fairy-types for Colossoil. Wish support from Pokemon like Chansey, Sylveon, and Clefable is incredibly helpful to keep Colossoil healthy, as it otherwise will be worn down rather quickly from entry hazard damage, potential status damage, and potential Life Orb recoil.
Choice Scarf allows Colossoil to act as a revenge killer and potentially a late-game wincon if its checks and counters are removed. Stone Edge provides strong coverage against Flying-types and certain Fire-types such as Pyroak and Talonflame, but Colossoil generally doesn't have room for the move, and it doesn't help with its issue with Tomohawk at all. Fire Fang does a hefty chunk of damage to Mega Scizor and Ferrothorn, but Colossoil struggles finding a moveslot for it and is usually better off using U-turn to switch to a partner in these cases. Iron Tail allows Colossoil to 2HKO Fairy-types it lures in such as Mega Altaria, Sylveon, and Clefable, but its shaky 75% accuracy makes this a subpar option. Toxic can be used to put opposing Tomohawk on a timer. Finally, a set with Flame Orb and moves like Fake Out and Facade utilizes Guts to its fullest potential, but it is generally worn down too quickly to be truly effective.
Checks and Counters
Tomohawk: Tomohawk can switch into any of Colossoil's moves and heal off any damage done with Roost. From there, Tomohawk can wear it down with Air Slash or Aura Sphere, set up entry hazards, set up Substitute, or use a boosting move.
Skarmory: Skarmory walls all of Colossoil's common moves thanks to its typing and can heal off any damage taken with Roost.
Mega Scizor: Mega Scizor's typing allows it to switch into Colossoil's common moves and heal off damage taken with Roost. It works well as a Knock Off absorber, as its Mega Stone can't be removed. Bulky Swords Dance variants of Mega Scizor can easily set up on Colossoil as well.
Grass-types: Grass-types such as Ferrothorn, Breloom, and Mega Venusaur heavily threaten Colossoil with their STAB moves, while Colossoil can't do too much in return besides U-turn out.
Fairy-types: Fairy-types, especially physically oriented ones such as Mega Altaria and Azumarill, easily force Colossoil out with their STAB moves and can use the opportunity to set up.
Fighting-types: Many Fighting-types, most notably Mega Heracross, can easily switch into Colossoil or simply revenge kill it, as they resist Knock Off and aren't threatened by Sucker Punch or Pursuit.
Water-types: Water-types such as Arghonaut, Gyarados, and Keldeo can stomach an attack from Colossoil and threaten it back with their STAB moves. Gyarados in particular can weaken Colossoil's Attack with Intimidate, is immune to Earthquake, and resists U-turn before it Mega Evolves, allowing it to check Colossoil quite easily throughout the match and Mega Evolve once Colossoil is defeated.