Kingler @ Life Orb

BAN.
The meta essentially relies on backbones comprised of Pokemon like Regirock / Gigalith / Garbodor / Weezing / Palossand / Claydol / Sandaconda to answer the tier's various threats, which is a big factor in driving how effective powerful Water-type wallbreakers like Clawitzer and Kingler are. They are basically very easy to position in battle as a direct result of the shape of the current meta, and the payoff is huge once they're in because their defensive checks, especially ones that fit easily on most teams, are few in number. Kingler also has a free slot to play with, meaning it can pick and choose which defensive check it needs to break past, ex. Knock Off into 4 SpA SF LO Ice Beam 2HKOes defensive Tangela over SR, Guzzlord can be answered by SD Body Slam or Superpower, etc. In many cases, wallbreakers as immediately powerful as Kingler tend to be slow enough that they can be pressured by faster, more offensive teams, but this doesn't hold true for Kingler given that Jolly/Naive variants outspeed the entire Scarf meta once Agility has been set up (and its setup here is easy thanks to Kingler's usable physical bulk, which makes it an amazing late-game cleaner). So, what you basically end up with is a customizable Pokemon (it currently runs with Agility / Knock Off / Liquidaiton / Body Slam in most cases, but if an answer to this set were to become more common, it could easily alter its set to accommodate for that change) with easily identifiable switch-ins that is able to cleave through both offensive and defensive teams alike, so imo, it's deserving of a ban. 
Clawitzer @ Choice Specs

BAN. 
If Kingler can be categorized as an 'unreasonably fast wallbreaker,' then Clawitzer goes the other way and can be called 'an unreasonably strong wallbreaker' that can basically spam Specs- and Mega Launcher-boosted attacks like Dragon Pulse and Dark Pulse as mid-ground options up until Water resists have been KOed and it's time to lock into Water Pulse. As I mention above, it is exceedingly easy to bring offensive Water-types like Kingler and Clawitzer onto the field and exert offensive pressure due to the shape of the meta, especially with the support of offensive pivots like Passimian, Togedemaru, and Archeops that bring in the Pokemon that Clawitzer abuses (ex. Palossand, Regirock, Sandaconda, etc.). Pokemon cited as splashable Water checks (ha) in this meta like Guzzlord, Whimsicott, Lanturn, etc. aren't actually able to answer Clawitzer in the long-term (ex. 252+ SpA Choice Specs Mega Launcher Clawitzer Dark Pulse vs. 36 HP / 220+ SpD Lanturn: 180-212 (45 - 53%) -- 86.7% chance to 2HKO after Stealth Rock and Leftovers recovery); that's not to say switching into all of Clawitzer's moves safely cannot be done, as there are Pokemon like SpDef Frosmoth and SpDef Articuno that are capable of this, but beating Clawitzer is often a matter of how accurately you're able to predict which coverage move it's locking into (which is a pretty shaky method considering what happens if you guess wrong and you don't have the means of narrowing its choices down like Protect/Spiky Shield + are not packing strong resists to its Dragon / Fighting / Water / Dark moves, ex. Toxicroak is OHKOed without prior damage by Dragon Pulse if you predict Clawitzer's attack incorrectly). Clawitzer also happens to hit a unique Speed, 217, and it doesn't have to sacrifice any power to reach this Speed despite it being as strong as it is, which is another factor that differentiates it from other slow wallbreakers like Aggron and Alolan Exeggutor that do have to make that trade. To sum up, Clawitzer is easy to get onto the field, standard checks to Water-types that actually fit on teams regularly can't answer it in the long-term due to how strong it is, and it's not even that slow despite its enormous damage output; Clawitzer is simply too strong for the meta, so a ban vote is warranted.
Omastar @ Power Herb 

BAN.
Omastar's presence in the meta is unhealthy, as the constraints it places on the meta are too much for just one Pokemon. It severely limits variance with regard to how many allowable team structures there are currently, ex. your Choice Scarf user must be faster than 458 Speed (Timid Omastar at +2) if you're lacking Fighting-type priority (basically, Heliolisk, Rotom, Togedemaru, and Gourgeist-Small are your picks here); Vacuum Wave (NP) Toxicroak is more common than SD sets partially due to Omastar's presence in the meta; you're less likely to see bulky Gourgeist or SpDef Togedemaru as a result of these slots being used for Choice Scarf more often than not; and, specially defensive / AV Guzzlord is common as a gluemon as a result of needing a secondary check to Omastar while also compressing that with a Poltergeist resist for Gourgeist + a Fire check + a strong resist to Heliolisk all into one slot. At the same time, the aforementioned defensive and offensive checks don't always answer Omastar reliably. Since Vaporeon rose to NU by usage on 4/1, Omastar doesn't actually have to run Meteor Beam anymore; it now has the option to run other items (ex. Wacan Berry and Chople Berry) with a set of SS / Earth Power / Surf / Ice Beam, which still threatens a chipped Guzzlord and Lanturn, but now also creates a scenario wherein Togedemaru can't actually RKO Omastar reliably and now instead activates Weak Armor. A big part of the issue is that Weak Armor + SS does not allow for Scarfed Pokemon to RKO Omastar, and so users have turned to priority from Pokemon like Vacuum Wave Toxicroak and various Mach Punch users like Gurdurr and Hitmontop as a result, which can be circumvented via Chople Berry. For those saying that Talonflame being out of the meta is terrible for Omastar, this is only partially true; some methods users have adopted in this Talonflame-less meta for facilitating Shell Smash setup include screens support, as well as pairing Omastar with a bulky Eject Button Pokemon that can eat U-turn. If you throw your bulky Eject Button Pokemon, whatever that may be, into U-turn pivots like CS Togedemaru and CS Passimian, this sends the EB mon out into Omastar as Passimian / Togedemaru / whatever else is still locked into U-turn, so they're forced to either U-turn again and activate Weak Armor or switch out as you Shell Smash. Omastar also simply does not have to Shell Smash on the turn you think it does; on the turn you hard-switch Whimsicott in to Encore Shell Smash or Scarf Gourgeist-Small to check Omastar at +2, it can simply Ice Beam then for example. Counterplay for Omastar simply hasn't been reliable this meta, so Omastar is therefore deserving of a ban. 
Ribombee @ Heavy-Duty Boots
DNB.
Ribombee is extremely powerful, with both QD and Choice Specs-sets being difficult to answer long-term with many of its checks lacking recovery (save for Wish SpDef Togedemaru and Roost SpDef Charizard), but the actual act of sweeping through teams with Ribombee relies on skilled play from the Ribombee user, given that checks like Spdef Charizard, Gigalith, bulky Steel-types like Togedemaru / Silvally-Steel / Stunfisk-G and even Magneton have to be removed or severely weakened prior to going in. And, not to mention, Lycanroc and other similarly powerful priority users must first be KOed before attempting a QD sweep, which to me is not really the hallmark of a Pokemon that lacks counterplay. Omastar's presence is actually part of why Ribombee is difficult to deal with right now; when Togedemaru is run with Choice Scarf rather than with SpDef investment in many instances for the express purpose of checking Omastar, suddenly Ribombee's best check now takes roughly 50% from +1 Moonblast rather than being able to act as a long-term check. 
Toxicroak @ Life Orb

DNB.
In a meta with Omastar and fat Fighting resists like Palossand and Weezing being quite common, NP continues to be Toxicroak's most common set, so building with it in mind usually only requires using a faster Fighting resist that can eat +2 Vacuum Wave. This isn't really a tall order to handle for PU; we've got options like Silvally-Fairy, Golbat (use 12 Atk-invested, 297 Spe Golbat!), Charizard, Ribombee, Xatu etc. that are feasibly able to check it even at +2. These checks are pretty common, and at the same time, Toxicroak provides a whole slew of useful resists that let it play a unique role in the meta as one Pokemon that is able to check offensive Water-types via its ability, absorb Toxic Spikes, pressure our SR users quite easily via its typing and coverage, and so on. Once Toxicroak starts running SD as often as it runs NP, it could start to be a problem, but at this point in the metagame, I feel that Toxicroak is easy enough for us to handle, even as we're forced to rely on very constrained building patterns as a result of the current structure of the meta.