Rises:

A+ ->
S-: Dragalge is the most potent breaker of this meta, with the presence of Stakataka only bolstering this with Focus Blast sets becoming much more common. Choice Specs, Substitute + 3 Attacks, Protect sets, all of them have massive potential to break with varying defensive flexibility. Dragalge heavily incentivizes people to build strongly around it, causing Doublade and even Bronzor to pick up in usage lately. It's certainly the biggest threat as a breaker in the meta.

A ->
A+: Escavalier is one of the beneficiaries of a Dragalge focused meta, taking neutral damage from Focus Blast and being bulky enough to prevent Choice Specs Dragalge from completely shattering it. RestTalk sets with Megahorn and SD are also becoming much more popular, ruining many teams that lack a Fire-type move to hit it with or at least a strong breaker that can break through its bulk.

A ->
A+: Vaporeon takes advantage of teams that only have a tool or two to break it, forcing them to play conservatively with their breakers so that they don't get swept by the aquatic demon. Although Vaporeon structures are still as exploitable as ever, it demands a newfound respect with how people tend to build more defensively to take care of powerful breakers.

A- ->
A: Both Choice Specs and Choice Scarf sets are very powerful, and the doubt between which set it could be makes it even better. Choice Scarf sets enable offense in a way it couldn't have operated before, with both Healing Wish and a very fast and strong STAB to fire off. Choice Specs, however, can completely ruin cores without a Dark-type, often 3HKOing even Steel-types with Expanding Force.

A- ->
A: Machamp is one of the best breakers we have in the meta. Although its held back by its speed tier, Flame Orb chip, and its physical bulk, it has amazing coverage in Close Combat, Facade (140bp), and Knock Off. These combine to make a threat that's nearly impossible to switch into, leaving only offensive checks to shut it down.

A- ->
A: Quagsire is a staple in many Stakataka cores, checking a ton of Pokemon such as Blastoise, Silvally-Ground, Tyrantrum, Drapion, Scrafty, SD Talonflame, and much more. While it can't set Stealth Rocks, options to pair it with a solid defensive option that can have been widely broadened, and make these defensive cores super solid on balance and bulky offense alike.

A- ->
A: Both removal and a breaking option, Tsareena's powerful Power Whip to take down most Pokemon is very well paired with a Knock Off to disrupt the Pokemon that don't. The compression with a Grass-type breaker as well as Rapid Spin allows this Pokemon to threaten many cores, and its speed tier puts it right above the most popular slow breakers in the tier such as Sirfetch'd, Machamp, Golurk, and Exploud.

B+ ->
A-: Toxicroak has been underrated for a while, completely dismantling cores of Mudsdale + Vaporeon as Toxicroak can take out Mudsdale with a +2 Life Orb Low Kick, and can easily use Vaporeon as setup fodder (even Toxic variants). The slight downswing of Talonflame usage also helps the fellow.

B ->
B+: Drapion is also very good, crippling Pokemon such as Mudsdale, Quagsire, Stakataka, and Talonflame with Knock Off while also running SD + Shuca Berry and Aqua Tail sets to OHKO Silvally-Ground without risk of dying. Its low attack means it can struggle to break some defensive cores, but its able to lure in and severely weaken many defensive Pokemon.

B ->
B+: Exeggutor-Alola is a good breaker in the current meta with a slightly higher speed tier than Dragalge, as well as access to Teleport and Sitrus + Harvest. Choice Specs sets have also seen exploration due to its speed tier. It also happens to take very little from common Pokemon such as Mudsdale, Vaporeon, and Rotom-Mow, easily taking the hit and pivoting in to threaten a kill.

B ->
B+: Heliolisk was underrated in my opinion last shift, and is moving back up as a threatening pivot and a Vaporeon abuser. Choiced sets are very potent, giving Heliolisk either an unmatchable speed tier or a strong special attack off of a massive array of coverage. Magnet or Heavy-Duty Boots sets are less exploitable, allowing Vaporeon to not scout what the Heliolisk user may do, which is a major weakness and a reason why it dropped before.

B ->
B+: Scrafty is a really good matchup fish into anything that isn't a Fairy-type, and even then, Throat Chop allows you to beat Hyper Voice Sylveon a good portion of the time. It also tends to not be dead weight in matchups where it cannot sweep due to its massive Special Defense stat making it a good general check to special attackers that aren't too strong or Ghost-types.

B- ->
B: Araquanid is a very solid Vaporeon abuser, inflicting Toxic on any Water Absorb Pokemon and threatening any non-Water Absorb Pokemon with a brutally powerful Liquidation. Although some Pokemon such as Vileplume and Dragalge can take advantage of the aquatic bug, its power and natural special bulk, as well as the fact it can't be burned, carry it up a subtier.

C+ ->
B-: Inteleon is an awesome guy, breaking most non-Water Absorb teams with a stellar speed tier. Even though its relegated to clicking U-Turn in matchups with Vaporeon or Mantine, this enables VoltTurn cores by creating predictable loops for the user of Inteleon.

C+ ->
B-: Togedemaru is a pretty nice defensive tool, completely shutting down Rotom-Mow by resisting Leaf Storm and being immune to Volt Switch. This allows Togedemaru teams to be the only teams that can reliably stop Rotom-Mow's mow-mentum without risking the death of an important defensive piece.

C ->
C+: Ferroseed is a funny little guy that sets Spikes, and without much competition either. Without Xatu seeing as much usage, Ferroseed has a good amount of bulk and a solid enough hazard stacking capability to end up disrupting teams with shaky hazard removal. Although it comes at the opportunity cost of not using another Steel-type, the opportunity cost of Garbodor over Weezing or Dragalge is also becoming quite high, and Ferroseed pairs with Dragalge quite nicely.

C ->
C+: Glastrier abuses Wish cores, especially Vaporeon, by Substituting on them and getting free SDs without a worry. This can make Glastrier the prime candidate for 6-0ing certain predictable cores, especially those that rely on Mudsdale as a primary physical wall.

C ->
C+: Ninjask does what Ninjask does best, and with Stakataka rising so much, its almost always the prime target to get either a Water-type or Fighting-type breaker in on for free. It's also able to revenge kill important Choice Scarfers such as Rotom-Mow, Indeedee-F, and Passimian, making it a perfect candidate for offensive teams that need a revenge killer to opposing scarfers.

C ->
C+: Silvally-Steel is a decent option for trying to get more speed into your team, giving options such as Defog and Parting Shot to keep up momentum, as well as outspeeding crucial threats such as Indeedee-F to threaten them after switching in.

C ->
C+: Stunfisk-Galar just allows for a crazy amount of compression, enabling offensive teams to fit more threats without fully giving up on fundamental balance building principles. It isn't perfect at any job it has, but it does stop momentum from Rotom-Mow, and is able to be a Ground-type and a Steel-type adequately enough.

UR ->
B-: A Ground-type that isn't completely fodder to Dragalge is a nice change, with a speed tier above Dragalge's and a threatening Glare to keep opposing Pokemon in check. Its also one of the best Stakataka checks with both Rocky Helmet and Shed Skin Rest to keep itself healthy enough to PP Stall Gyro Balls and threaten to KO with Earthquake.

UR ->
C+: Another Pokemon that screams "compression", it is able to provide removal and a check to both Blastoise and Silvally-Ground in one slot. Not much more to say.

UR ->
C: Jellicent is most well known for Taunt + Status and Hex sets, which can destroy traditional balance cores that rely on Wish or Heal Bell to keep themselves sustained.

UR ->
C: Drampa is an okay breaker with Roost + Berserk, but it also is used as a niche Defogger to keep Grass- and Water-types in check.

UR ->
C: One of the more popular suicide leads nowadays, it can Stealth Rock and often get off another attack with Weak Armor activated after Sash.
Drops:

S ->
S-: Talonflame just isn't as good as Rotom-Mow, even with it still being one of the best Pokemon in the tier. Its usage has gone down with a lot of breakers such as Sirfetch'd and Specs Sylveon seeing less usage than they have previously, and its just not as important to use when facing down traditional Mudsdale + Vaporeon cores. Innovation is happening with Taunt + Toxic sets, but these have their own issues.

S ->
S-: Silvally-Ground is just not as good as Rotom-Mow (again), and is getting more respect in the builder. Mudsdale gives it a lot of competition for the Ground-type slot, and it doesn't find itself completely mowing through teams as it did right when Stakataka dropped. Its still very potent and requires a lot of preparation, but its not quite S-tier.

S- ->
A+: Copperajah is just a little hard to justify. Its one of the best ways to break in the tier, but its doesn't really outdo either of the other Steel-types defensively in any regard. Stakataka can handle Fire-types a lot better, and Escavalier can handle Fighting- and Ground-types better as well. Copperajah is in an awkward middle spot defensively, where its solo-Steel typing isn't a boon anymore.

A- ->
B+: Decidueye just hasn't been performing quite as well lately, with Ghost-types in general becoming less and less meta. Poltergeist is rather easy to check, and Spirit Shackles is just not strong enough to break generic physical walls. Special sets break rather well, but struggle due to its Speed-tier and reliance on Leaf Storm to break.

A- ->
B+: Golurk is still a good Pokemon, but the other Ground-types give it a whole lot of competition for the slot. Its quite slow as a breaker, and therefore easy to revenge kill, but it also struggles against generic physical walls like Vaporeon and Mudsdale. Its still very potent though, and it at least has the speed tier to revenge kill Dragalge and pressure teams by outspeeding common Steel-types.

A- ->
B+: Guzzlord has just not seen a lot of usage. Choice Specs sets have been getting more usage in NUPL, but its just overall not that great right now. It has a speed tier just below Dragalge, and it struggles to break a lot of defensive cores regardless.

B+ ->
B: Exploud just struggles against Vaporeon and Sylveon if it doesn't have Choice Specs, and Choice Specs sets are vulnerable to Steel-types that can pivot in and around its coverage moves.

B+ ->
B: Passimian is just not as strong of a scarfer due to the fact that there's other Choice Scarf users like Rotom-Mow and Indeedee-F, as well as several strong Fighting-types as competition with Sirfetch'd, Machamp, and Toxicroak.

B ->
B-: Rhydon is still a decent breaker, but it doesn't do a great job as a Ground-type as it takes a ton of damage from Stakataka's Gyro Ball and can't act as a physical sponge for many attackers such as Fighting-types and Power Whip Pokemon such as Copperajah and Grimmsnarl.

C ->
UR: Aurorus should stay in ORAS, dumb idiot pokemon

C ->
UR: Xatwho? This thing sucks.