As part of the new legendary foursome (don't forget PONY, people!), Terrakion boasts a unique type combination and some pretty beastly base stats to take advantage of it offensively. The great type coverage granted by its STABs alone essentially allows Terrakion to do whatever it wants with its last two moveslots. Because of these factors, Terrakion can be one of the best stat-boosters in the game, one of the best Choice Band users in the game, or one of the best revenge killers in the game when equipped with a Choice Scarf. With this offensive diversity, Terrakion is one of the best offensive threats in the game that every team should be prepared for, and everyone should consider using.
Stop me if I'm talking too much about how great Terrakion's offensive typing is, but the Choice Band set truly exemplifies just how fantastic its STABs really are. Choice Band Terrakion essentially boils down to, "Click its appropriate STAB for the situation and watch things take massive amounts of damage." Additional factors, such as great Speed, a resistance to Stealth Rock, and solid bulk make Terrakion arguably the best Choice Band user in the OU metagame.
Because Terrakion's STABs are just so balling, the last two moves in the set serve very limited functions. X-Scissor hits the bulky Psychic-types a bit harder than Stone Edge does, while also having the upside of being 100% accurate. Sacred Sword is a solid option in the fourth moveslot for situations in which you want to use your Fighting-type STAB without being forced to lower Terrakion's defenses. Quick Attack, normally a terrible option on just about everything that learns it, is somewhat viable on Terrakion. Because Terrakion doesn't need a coverage move in that last slot, Quick Attack becomes a solid situational, last resort move if you need to knock that last 15% off Latios.Team Options & Additional Comments >>>
While other Terrakion sets are more focused towards sweeping and punching holes, this set focuses more on supporting its teammates by setting up Stealth Rock. Terrakion makes for an excellent user of Stealth Rock due to the many switches it forces with its heralded STABs. This Terrakion set is best used in the lead position, as it can get up Stealth Rock right off the bat and threatens common weather inducing and entry hazard-setting leads. With Taunt, it can also stop most setup sweepers that might choose to lead in their tracks. Another reason why Terrakion is an excellent user of Stealth Rock is that it can beat a common spinner—Forretress—as well as Espeon and Xatu which reflect Stealth Rock and Taunt. Very few Stealth Rock users can beat Espeon and Xatu, so this is a major advantage over other users. In addition, Terrakion is pretty much the only Stealth Rock user not named Tyranitar that is legitimately threatening to sun teams and their most common methods of preventing Stealth Rock from being set up, namely Forretress and Xatu. Stone Edge and Close Combat hit most of a sun team for heavy damage and Stealth Rock is a pain for Fire-types such as Volcarona, Victini, and Ninetales on said teams. Terrakion is also not setup bait for opposing entry hazard setters, unlike Ferrothorn and Forretress. Swords Dance can be used over Taunt to bluff one of the more traditional Terrakion sets and to provide immediate pressure in the lead position and later in the game after Stealth Rock has already been set up. As a final note, Stealth Rock Terrakion is often unexpected, which gives it more opportunity to set it up.Team Options & Additional Comments >>>
Besides Gliscor, Slowbro, Landorus-T, and a few obscure counters that struggle to reach even 2% usage in OU, the only way to deal with Terrakion is through status or revenge killing. Now, imagine if it had a way to get around status users and revenge killers—that would be a sight to behold wouldn't it? If this behemoth managed to set up, the opponent would surely be stuck between a rock and a hard place. Well, why are you still imagining? Substitute + Swords Dance Terrakion does just that! With Substitute, the terracotta warrior can now block those ever so annoying Thunder Waves, Will-O-Wisps, and Toxics. Furthermore, Substitute acts as a buffer against annoying revenge killers, such as Alakazam and Starmie, who now must waste a turn breaking the Substitute, and are destroyed by a powerful STAB move in return. Most importantly, though, Terrakion is cushioned from priority moves, such as Scizor's Bullet Punch, and with its newly found fly swatter, can crush the red bug in cold blood.
While Substitute is certainly the distinguishing move on this set, it is important to note that without Terrakion's fantastic stats, movepool, and offensive typing, this set wouldn't be nearly as effective. Swords Dance skyrockets Terrakion's Attack to terrifying levels. Even Gliscor and Slowbro must think twice about coming in, because if they are damaged prior to the encounter, a +2 Stone Edge can still break through. Its Fighting- and Rock-type STAB combination provides fantastic coverage, resisted only by a select few lower-tier Pokemon. Close Combat is Arceus's gift to Fighting-types; backed by Terrakion's immense power, it is one of the most fearsome moves in the metagame. Stone Edge rounds off this brute's set, allowing it to barbarically tear apart opposing teams.Team Options & Additional Comments >>>
As mentioned in the Overview, Terrakion has amazing offensive typing, and combined with its bulk, has the freedom to do what very few other Pokemon in the game are able to: run a double boosting set. This gives Terrakion the versatility to be a fantastic weapon against both offensive and defensive teams. Against offensive teams, Rock Polish allows Terrakion to use its great STABs and the boost from Life Orb to run through them. Against slower, defensive teams, Terrakion can amplify its raw power with a Swords Dance, since it is unlikely to require the Speed boost. Also, it isn't that uncommon to find yourself in a situation where you are able to boost both Speed and Attack.
Air Balloon versus Life Orb is the biggest question you have to ask yourself when using Double Boosting Terrakion. Air Balloon is extremely useful for setting up in those frequent situations where you need to avoid an Earthquake. The most obvious scenario is getting an extra boost against Gliscor. Life Orb, on the other hand, adds to Terrakion's raw power, allowing it to nail a number of KOs that it normally wouldn't get. It really comes down to personal preference and which item is best suited for your team. Choose wisely!Team Options & Additional Comments >>>
Many of the same factors that make Terrakion an amazing Choice Band user lend themselves to making Terrakion one of the best Choice Scarf users in the game as well. Its blazing Speed allows it to safely revenge kill some of the biggest threats in the game. The moves are self-explanatory if you read the Choice Band set. Close Combat and Stone Edge are your two powerful STAB moves and X-Scissor covers bulky Psychic-types. The fourth slot is, once again, essentially useless, so run whatever you feel like. Rock Slide is the first option merely because its ability to flinch can be useful in a pinch, while other options such as Earthquake provide redundant coverage.Team Options & Additional Comments >>>
I'm sure you've already looked through Terrakion's moveset and thought, "Whoa it learns Calm Mind!" Yes, yes it does learn Calm Mind. It's arguably Terrakion's best set; however, for some reason, the Quality Control guys won't let me list it first in this analysis. In a similar (and more serious!) vein, Terrakion also learns Work Up. The only use for it would be to lure Gliscor into a +1 Hidden Power Ice. The problem with that idea is that using Work Up as your opponent switches to Gliscor is a dead giveaway that you're rocking Hidden Power Ice. If you want Terrakion to act as a Gliscor lure, you're much better just pumping a ton of EVs into Special Attack so that it doesn't see it coming until it's already dead. Terrakion can also make use of Protect on some sets, which can be used to scout against Choice-locked Pokemon such as Rotom-W and Scizor; however, in order to use this, it sacrifices an important moveslot for a move that is only useful in a niche situation, and as such Protect is usually inferior to Terrakion's standard options.
Terrakion also learns Taunt, which obviously makes a Taunt/Swords Dance set an option. However, most of Terrakion's counters are simply going to attack it straight up, meaning there are very few situations in which Taunt would be anywhere near useful. Maybe against Skarmory I guess? Yeah, that makes sense.
Checks and Counters
If there was an award in OU for "most difficult Pokemon to switch into," here's your winner. Slowbro is probably the best check you'll find in OU, although a Stone Edge boosted by a Choice Band or a Swords Dance boost will hit like a truck. Gliscor and Landorus-T are also good checks, though they will be taking a ton from Stone Edge from those sets. Mew, Reuniclus and Jellicent also fall into the similar category. There is light at the end of the tunnel though; Terrakion needs to hit two consecutive Stone Edges to KO any of these Pokemon. Hippowdon can also tank a hit and Slack Off. You may be inclined to use Skarmory as your Terrakion counter, but despite its good Defense, Skarmory is ravaged by a Close Combat from the Choice Band or Swords Dance set, allowing it to only deal with Terrakion that lack Attack boosts.
Terrakion can be hard to check because of its great Speed. Scizor and Azumarill are two Choice Band users that can stop any Terrakion set dead in its tracks with their STAB priority attacks. Infernape can also do a good chunk of damage with Mach Punch; Conkeldurr can do the same and can also, at high health, survive a non-boosted Close Combat and go for the OHKO with Drain Punch after Stealth Rock. Latios and Tornadus can outspeed and hit Terrakion hard with Psyshock or Hurricane, respectively. Gengar and Starmie can smash it with Focus Blast and Hydro Pump, while Espeon can hit it hard with Psychic. Gengar deserves a special mention because it can Disable Stone Edge, crippling Terrakion instantly. Dugtrio does what he does best and can trap Terrakion with Earthquake. Wobbuffet knocks Choice-locked versions of Terrakion out of the park and will make them think twice before spamming Close Combat. Choice Scarf users such as Rotom-W and other Terrakion are also fantastic checks.
Ironically, Terrakion's best counters litter the lower tiers, with examples being Golurk, Nidoqueen, Claydol, and Tangrowth. If you're feeling desperate, then one of these is your best bet.