When looking at Latios's disappointing base stats, particularly his subpar bulk and average Special Attack when compared to the rest of the tier, one might question why he should be used in Ubers. Latios's typing grants him weaknesses to the Dragon-, Ice-, Ghost-, and Bug-type attacks rampant in the metagame, and only offer resistances to Grass-, Electric-, Water-, Fire-, Psychic-, Fighting-, and Ground-type attacks in return; his STABs also have little offensive synergy. He lacks the ability to hit Steel-types hard, and he is forced to use the weather-reliant Surf, Hidden Power Fire, and Thunder for coverage.
Then what is it that makes him one of the most deadly sweepers in the game? The answer is simple: Soul Dew. The boost Soul Dew provides to Latios's mediocre stats allows him to smite his fellow dragons with ease. Raising Latios's bulk to respectable levels and boosting his Special Attack, Soul Dew allows him to take full advantage of his Speed, ability, and resistances and rival the titans that terrorize the Ubers metagame. However, Soul Dew will not make Latios perfect; his movepool remains barren, and his physical defense feeble. He also faces competition from Latias, who boasts better Defense and who too can benefit from Soul Dew. Not all is lost for Latios though. By taking advantage of his colossal Special Attack and an ironically distinguished support movepool, Latios can remind all of his forgotten power.
Latios's respectable Special Defense, huge Speed, and monstrous Special Attack allows him to effectively run a Calm Mind set. Calm Mind is the crux of the set; by powering up his already high Special Attack while bolstering his defenses, it makes him less prone to being revenge killed. Psyshock and Dragon Pulse form the bread-and-butter of the set, and allow Latios to essentially go mixed, while also providing Latios with a way to severely dent the pink blobs that might try to stop his sweep.
However, if you feel that Psyshock provides little coverage and your team has a way around Blissey and Chansey, you can opt to use either Surf, Thunder, or Roost in the second moveslot. In the rain, Surf brings down Excadrill, Heatran, and Steel Arceus. Thunder hits Steel-types neutrally, while also giving Latios a handy 30% chance to instantly cripple a Pokemon for the rest of the match. However, if you feel that neutral coverage on Steel-types is unnecessary, then you can opt to use Roost which lengthens Latios's longevity and easily allows him to gain more than one Calm Mind boost.Team Options & Additional Comments >>>
This Latios variant attempts to take advantage of the free Calm Mind boost offered by Soul Dew to instantly bombard the enemy with powerful special attacks. Draco Meteor's power is enormous, and boasts the ability to OHKO virtually everything that doesn't resist it not named Blissey or Chansey. Thunder allows Latios to ruin Kyogre and Manaphy, while also providing decent coverage, but its reliance on rain might render it useless on certain teams. Grass Knot is a suitable alternative; while it is incapable of dealing damage to Manaphy and enemy Steel-types, it can take an enormous chunk of health out of opposing Groudon, Kyogre, and Tyranitar, regardless of the weather.
The third move allows Latios to hit Steel-types: Hidden Power Fire maims enemy Forretress, Ferrothorn, and Excadrill in the sun at the cost of losing the Speed tie with other Latios and Latias. On the other hand, Surf keeps Latios's ability to Speed tie with these Pokemon in exchange for leaving him at the mercy of enemy Ferrothorn. The last slot lets Latios use a STAB move that doesn't instantly cripple him. Dragon Pulse is a strong, reliable STAB, while Psyshock gives Latios the ability to damage Blissey and Chansey. However, if you feel that an extra STAB move is unnecessary, you can opt to use Roost to heighten Latios's longevity.Team Options & Additional Comments >>>
Latios's typing, ability, high base Speed, and access to Memento enable him to distinguish himself as an exceptionally talented dual screen user. Light Screen and Reflect enable Latios to cushion both himself and his team from the enemies' attacks for eight turns. With Memento in his arsenal, Latios can sacrifice himself to lower the offensive stats of an enemy even further, allowing a teammate a free switch-in. The third moveslot choice depends on what the team needs. If Latios's only goal is to cripple an opponent, Draco Meteor lets him do heavy damage before lowering its attacking stats. In addition, Draco Meteor prevents Latios from being destroyed by Taunt and stops Rayquaza from setting up on him. Alternatively, Latios can easily set up screens more than once a match, and Roost enables him to heal himself to do so even more reliably.Team Options & Additional Comments >>>
Using Dragon Dance on a specially based Latios might sound absurd, but it provides a useful Speed boost that allows him to outrun and KO almost everything in the metagame. Latios's unique typing is an advantage in this case, as it allows him to take advantage of a stray Surf or Fire Blast to set up with Dragon Dance. These unique traits allow Latios to become a potent cleaner more than capable of striking fear into all teams late-game.
Dragon Pulse is strong, reliable STAB that will dent everything barring Chansey and Steel-types after Stealth Rock. Thunder assuages Latios's issues with Steel-types in the rain, and provides nice coverage to complement Dragon Pulse. Grass Knot, while incapable of hurting Steel-types, maims Tyranitar, Groudon, and Ground Arceus, scoring OHKOes on the latter two Pokemon and 2HKOes on Tyranitar. The last slot further improves Latios's coverage. With Psyshock, Latios gains the ability to muscle past Chansey, as the move will 2HKO after Stealth Rock. Psyshock, however, leaves Latios vulnerable to both Excadrill and Ferrothorn, two Pokemon that have little trouble stomaching the rest of Latios's attacks. Surf easily takes care of Excadrill, OHKOing it in rain, while Hidden Power Fire will OHKO Ferrothorn and Excadrill in sun. These moves also have nice coverage alongside Thunder and Grass Knot, respectively.Team Options & Additional Comments >>>
Latios lacks any noteworthy options to use outside of those already listed. If you have an enormous aversion to Tyranitar and wish to maul his body around the battlefield like the fate of Hector, you can run Hidden Power Fighting. As it can also hit Ferrothorn, Excadrill, and Heatran, regardless of weather, it is not completely situational. It's not recommended, though, as it is fairly weak even against targets it hits super effectively.
Checks and Counters
Like many other Ubers Pokemon, Latios has no true "counter". There are, however, some that stand out from the pack. Dark Arceus, Chansey, Ho-Oh, and Lugia are not 2HKOed by any of unboosted Latios's moves if Stealth Rock is not up. Dark Arceus stands out from this list of checks because it can also OHKO Latios with a STAB, super effective Payback, or set up with Calm Mind.
You can also look to taking advantage of Latios's reliance on weather to hit enemy Steel-types. For example, Ferrothorn and Heatran are all capable of walling a Latios in detrimental weather because Latios cannot 3HKO Heatran with a sun-weakened Surf or 2HKO Ferrothorn with a rain-weakened Hidden Power Fire. Excadrill distinguishes itself from the other Steel-types by being able to actually remove Latios from the match via Mold Breaker Earthquake if Latios is in the wrong weather. Jirachi does a similar job, but doesn't really care about which weather it is in, as it can avoid an OHKO from sun-boosted Hidden Power Fire and annoy Latios with the combination of Thunder Wave and Iron Head.
If you find yourself unable to pack any of these Steel-types on a team, then you might as well resort to revenge killing Latios. While Latios's Speed is high, it is susceptible to priority. Therefore, strong priority users, such as Extreme Killer Arceus, Scizor, and Giratina-O can finish off weakened Latios. In rain, Kingdra can outspeed and KO Latios with its STAB moves; Kabutops can do the same, although it needs Stealth Rock damage. Additionally, although Latios can normally cushion special attacks thanks to Soul Dew, he is hardly impervious to them in any way; strong special attacks can still plow through his sky-high Special Defense. Choice Scarf Dialga and Palkia can revenge kill Latios that lack a Calm Mind or Light Screen boost with STAB Draco Meteor.
Ghost, Rock, and Steel Arceus, while not nearly as effective as Dark Arceus, are all capable of stomaching incoming Draco Meteors, and can easily set up Calm Mind or outright KO Latios with their strong physical STABs. They must be wary of Latios utilizing dual screens or opposing Calm Mind Latios though, as they will be setup bait instead. Calm Mind Latios can be taken down by adding Roar to any of Calm Mind Arceus's movesets.
All Latios variants share a crippling weakness to Dark-type moves, Pursuit in particular. Should you be able to switch a Pursuit user into Latios, it will be able to checkmate Latios. Tyranitar and Scizor distinguish themselves with their ability to not only threaten Latios with their STAB, but also to tank a Draco Meteor with ease.
Lastly, Wobbuffet can easily annoy every Latios variant that exists. It turns the Calm Mind, Dragon Dance, and dual screens sets into setup bait, and boasts the ability to revenge kill Latios that have already used their STAB Draco Meteor.