Set Description
Forretress sets Spikes up against a wide variety of Pokemon and can often do so multiple times a game due to its bulk. With maximum special bulk and Leftovers, Forretress shields itself as much as possible against Magneton and greatly increases the amount of Pokemon it can use Spikes on, like Milotic and Zapdos. In addition, this allows Forretress to better combat defensive Starmie trying to remove Spikes. Almost all Forretress run Rapid Spin due to Spikes's prominence in the metagame. Beware of teams likely to have defensive Gengar, as opponents will often liberally bring it in on Forretress with their Spikes laid to prevent losing them as well as to force Forretress out.
After Spikes and Rapid Spin, Forretress's options open up quite a bit, letting it defeat some of its counters or be a general threat with Explosion. Hidden Power Bug helps against Claydol and Starmie as well as Celebi and Tyranitar. It is a guaranteed 3HKO at least on both Claydol and Starmie—this discourages them from performing their duty of removing Spikes. It also 2HKOes all variants of Celebi, which is useful due to Forretress teams frequently being weak to Celebi passing Calm Mind or Swords Dance. If Gengar tries to block Rapid Spin, Hidden Power Bug can remove it after sand if it was hit by Pursuit upon switching out, easing Forretress's ability to keep Spikes off the field. Earthquake Forretress OHKOes most Magneton and damages Metagross, Tyranitar, and Jirachi. If you suspect Magneton is on the opposing team, aggressively using Earthquake as it comes in can be a game-winning play. Earthquake's utility against Metagross can be very important to stop it, especially Choice Band sets, from accumulating chances for Meteor Mash boosts and potentially steamrolling Forretress's team, especially since the best common option to phaze Metagross is a Roar Swampert that lacks its own Earthquake. Earthquake also gives Forretress an option to combat Dragon Dance Tyranitar and Substitute non-Fire Punch Jirachi in desperate situations. Forretress can additionally use Explosion, which notably prevents setup from Pokemon such as Curse Snorlax, Dragon Dance Gyarados, and Dragon Dance Salamence. It can additionally eliminate threats coming in, such as Moltres and Charizard. Smart uses of Explosion include against incoming Claydol and Starmie to keep Spikes up, on paralyzed threats to end turns—since Explosion prevents action by slower threats in ADV—or even against Rock-resistant Pokemon or walls to set up an Aerodactyl or mixed Salamence sweep. Be careful of Gengar switching in, however. Picking two of Hidden Power Bug, Earthquake, and Explosion is up to personal preference outside of teams with specific needs.
Team Options
Forretress needs specific support from its teammates in order to be most effective: Pursuit support for removing Gengar, special walls for the strong threats like Moltres it often attracts, good physical answers for the threats that try to set up on it, like Salamence and Snorlax, and Pokemon that take advantage of the extra residual damage Spikes provides. Tyranitar is by far the best partner for Forretress. It not only sets up the sand that helps make Spikes damage stick, but it also Pursuit traps Gengar, acts as a solid answer to Moltres as well as some Snorlax, and takes advantage of Spikes with Roar or a well-timed Focus Punch. With smart play, Pursuit Tyranitar can remove Claydol and Starmie to prevent Rapid Spin, but be careful of their Earthquake and Surf, which will typically 2HKO Tyranitar. However, Forretress's Pursuit trapper does not have to be Tyranitar—Umbreon and Houndoom are other options that can also free up Tyranitar to run a physical set, such as Choice Band, Dragon Dance, or bulky physical attacker, that benefits more from Spikes. Forretress can also be run without a Pursuit Pokemon if it has additional assistance from another Rapid Spin user such as Claydol, though this pairing is relatively niche. Gengar is another good Forretress teammate because it not only greatly appreciates Spikes, but it also helps keep Spikes up against Claydol, Starmie, opposing Forretress, and even the rare Donphan. A Forretress, Gengar, and Tyranitar core is commonly used to take advantage of Spikes and keep them up against spinners while also finding opportunities to trap and remove them.
As for special walls, the standard on many Forretress teams is Blissey, often with Wish to help Forretress deal with residual damage. It also commonly runs Counter, sometimes with Wish as well, due to Forretress teams generally being weak to mixed sweepers such as Salamence and Tyranitar. This point is especially true when the team does not have strong physical walls. However, the special wall can easily be Jirachi, which has an easier time fitting Wish, works well with Pursuit trappers to prevent Gengar from burning it, and shores the team up against physical threats such as Metagross, Fighting-type Pokemon, Aerodactyl, and Tyranitar. Wish support in general from not only Blissey and Jirachi but also Salamence and Umbreon can be helpful to keep Forretress and its teammates healthy, especially if Spikes can't be removed as easily. Celebi can fill the specially defensive role, as it is stronger against defensive Water-types such as Rest Suicune and switches into Leech Seed from opposing Celebi and Venusaur. Beware of offensive Water-types such as fast Calm Mind Suicune and Starmie hitting hard or freezing with potentially boosted Ice Beam, however. Specially defensive Roar + Rest Zapdos is a good choice on these teams, as it provides additional support against Calm Mind Pokemon like Celebi, Jirachi, and Suicune and mixed Salamence, which often tries to take advantage of Forretress. It also is great as additional support against offensive Water-types, such as the aforementioned Suicune and Starmie, which love to spam Hydro Pump against Forretress and its common teammates. Furthermore, it stops Gyarados from taking advantage of Forretress's passivity. Zapdos can even use Light Screen to give Forretress a better chance against Magneton.
For physical walls, Forretress appreciates Pokemon like Swampert and Flygon to help the team handle physical threats such as Tyranitar and Salamence. Defensive Metagross, Milotic, and bulky Roar Suicune can also work on some Forretress teams, as they check the Rock-type threats and Metagross that can break apart Forretress teams. Milotic is especially nice here, as it also is a fantastic counter to Fire-types such as Moltres and Charizard as well as mixed Salamence, which prey on Forretress and its common teammates. Dugtrio can also be helpful on some Forretress teams because it can trap threats such as Calm Mind Celebi, Calm Mind Jirachi, Dragon Dance Tyranitar, and Heracross—dangerous Pokemon that are typically difficult to handle for many Forretress teams.
Forretress really appreciates Pokemon that can take advantage of Spikes. Roar is a good option to repeatedly force Spikes damage on foes, and it can easily be fit on essential teammates, such as Pursuit Tyranitar, Swampert, Suicune, and even mixed Salamence. Outside of Roar users, Zapdos, physical Tyranitar, Gengar, Salamence, Aerodactyl, Venusaur, and Moltres work well. Aerodactyl is especially strong, as it not only benefits from a good Skarmory answer and Pursuit support, but it also cleans effectively with Spikes and helps against Calm Mind and Swords Dance Baton Pass Celebi with Hidden Power Bug. Moltres is a nice middle-ground switch-in against Gengar, as it is immune to Gengar's Will-O-Wisp and takes a pittance from Grass-type coverage and Focus Punch meant for catching Pursuit Tyranitar. Moltres, Salamence, and Gengar also provide a switch-in to Heracross—a dangerous threat that takes advantage of the lack of Drill Peck Skarmory on these types of teams. Very aggressive Forretress teams can also run their own Fighting-type Pokemon such as Medicham, Breloom, or Hariyama, as its role compression of Spiker and spinner allows TSS teams to fit a variety of Pokemon.