Differentiating itself from its fellow Bug-types with access to Quiver Dance, Masquerain cements its primary niche as the only user of the move with access to Baton Pass, which allows it to pass its boosts to a partner. Finding opportunities to set up can be a difficult task, largely due to Masquerain's crippling 4x weakness to Stealth Rock that is further compounded with a defensive typing that is surprisingly easy to take advantage of. It has access to a useful ability in Intimidate however, which with the help of Roost gives it the chance to set up against a variety of physical attackers and defensive Pokemon. Even when it manages to set up though, Masquerain by itself does not make for a good sweeper and relies on the partners it passes to in order to keep up the offensive momentum; using it to its utmost potential requires team support in the form of Pokemon that can take advantage of the boosts that it provides.
This set takes a simple goal of setting up as many Quiver Dance boosts as possible so that a teammate can perform a sweep afterwards. The combination of Intimidate, Special Defense boosts from Quiver Dance, and a typing that grants Masquerain some useful resistances gives it the opportunity to set up on most defensive Pokemon; including Alomomola, Tangela, Seismitoad, Misdreavus, and Miltank, as well as on Choice-locked Fighting- and Ground-type Pokemon like Golurk and Sawk. It should be taken into account that it will often take a bit of prediction to find opportunities to pull off a successful pass with the general prevalence of Choice Scarf users. Once Masquerain has received enough boosts, then the most urgent thing to do is to pass to a recipient as soon as it can.
Baton Pass serves an important role here, as not only does it pass Quiver Dance boosts but making timely use of it can work wonders towards easing prediction and gaining momentum when scouting common switch-ins such as Choice Scarf users or phazers. In terms of attacking, Bug Buzz is useful in the fact that it hits moderately hard after a number of boosts, while also serving as a tool towards bypassing some phazers such as Zweilous and Grumpig. Air Slash serves as a secondary option that can help Masquerain fend off Primeape, while also being able to nab an OHKO on Scolipede after a Quiver Dance boost. It should be taken into account that while attacking isn't particularly important for this set for the most part, running one of these moves does prevent Masquerain from being complete Taunt bait. Roost is one of Masquerain's most vital assets, as it helps increase its longevity mitigate its crippling weakness to Stealth Rock, potentially giving it more opportunities to set up later.Team Options & Additional Comments >>>
On paper, Masquerain has the capability to take a more offensive approach with Quiver Dance and attempt a combination of sweeping and Baton Passing. Such a set would be along the lines of Quiver Dance / Bug Buzz / Air Slash / Baton Pass with Life Orb to somewhat separate itself from Butterfree. Even then though, it isn't as fast or powerful as Butterfree and doesn't have the ability to put a counter to sleep, making it somewhat inferior in this role. Coverage moves like Hydro Pump and Giga Drain can work, as the former can get some nice hits on Pokemon that otherwise don't take much from Masquerain's STAB attacks such as Bastiodon and Flareon and the latter can score super effective hits against Rock-, Ground-, and Water-types such as Golem, Seismitoad, and Alomomola while regaining some health. Toxic and Stun Spore could be nice to cripple walls that Masquerain can set up on even further. This could also be beneficial for crippling Taunt Misdreavus as they normally expect to stop Masquerain from setting up without any consequences. Scald seems like a somewhat effective option because of its ability to inflict burns, something especially helpful in gaining setup opportunities, but it is rather weak. Masquerain can make use of both Rain Dance and Sunny Day, being able to fire off rain-boosted Hydro Pumps with the former, make use of SolarBeam with the latter, and provide momentum for teams based around either with U-turn and Baton Pass. However, Masquerain is quite slow and doesn't benefit from the common members of the weather teams all that much. Tailwind seems like a potentially useful support move, but Masquerain is often eclipsed by other users and can already pass Speed boosts with Quiver Dance.
Checks and Counters
The best way to counter Masquerain is to prevent it from getting a successful pass off. This part can often be tricky, as there are few Pokemon that can outspeed it after a Quiver Dance boost. One important way of making its job difficult is through the use of Stealth Rock, as chipping away 50% of its health makes it much more difficult for Masquerain to get around its checks and counters, set up, and avoid getting picked off. The single best and most reliable way of shutting it down is through the use of phazers, particularly the ones that aren't weak to its STAB and don't mind taking a boosted hit in response. Pokemon such as Bastiodon, Camerupt, Munchlax, and Lickilicky can take boosted hits with ease and ruin its strategy with Roar or Dragon Tail, though the latter has to beware of Substitute. Taunt from the likes of Skuntank and Misdreavus can also temporarily stop it from doing its job.
On a more offensive approach, Swellow is initially a very strong response towards stopping Masquerain. Swellow can not only come in on anything Masquerain can do but also outspeed it even after a Quiver Dance boost and OHKO with Facade or Brave Bird. Charizard can also safely come in on Masquerain, outspeeds after a boost, and easily threaten it with Fire Blast. Making use of Choice Scarf users that can outspeed and OHKO Masquerain after a boost can also work wonders. Choice Scarf Braviary is an excellent answer to Masquerain as not only can it outspeed and OHKO with Brave Bird, but it can also discourage Masquerain from switching in on something that it can set up on due to the possibility of a timely double switch in an attempt to activate Defiant. Choice Scarf Primeape and Sawk are other good examples of such checks, as they can come in on anything safely other than Air Slash and proceed to OHKO Masquerain with Stone Edge. Answers also include Garbodor, which not only can deal a lot of damage with Rock Blast but can utilize Clear Smog to negate any boosts Masquerain or the receiver has and Toxic to cripple the receiver as it comes in. Golem and Piloswine are also able to threaten Masquerain with their respective multi-hit STAB moves, but they won't be able to stop it from Baton Passing out unless Masquerain is weakened enough to be picked off by Ice Shard in Piloswine's case.
There are other measures that can be taken if you cannot prevent Masquerain from setting up and Baton Passing to a recipient. If necessary, you could try to predict what Masquerain will pass to and attempt to OHKO or status the recipient in some manner, but such a strategy isn't particularly reliable and should only be treated as a last resort.