I think EBook's position right now is hard to make heads or tails of. People's opinions of it tend to heavily lean one way or the other in my experience; between BB recoil, a weakness to rocks, sometimes further cutting its HP with substitute, and really limited OHKO power, it often seems like its turns are more often spent setting up and clicking Roost than ever actually attacking. Coupled with the fact that a bunch of the upper tiers outspeed and threaten it – Weav, Dragapult, Volt Koko, Tornadus-T, etc – it can be an easy mon to dismiss. On the other hand, setup with Tinted Lens BB feels straight unfair at times, and many of its "paper checks" (excuse the pun) fall flat in game. Whether this means landing one Gunk poison on Zapdos, SubCoil beating Ferrothorn, defense raises allowing you to beat Melmetal/Weavile, PP stalling Skarmory behind a sub (or just critting it), +1 BB -> +0 BB having a roll to break Toxapex (or get rocks up), etc... well, it's surprising how little is actually safe vs it, with a lot of stuff like Zapdos and certain Steels being set-dependent answers. It's not like it has a shortage of entry opportunities, either, being able to hard switch into mons like Lando/Clef/Corv/Argh/Kartana if rocks aren't up. Personally I lean towards it being slightly overtuned still, though as I said, I think it's a trickier case.
The much more clear-cut mon in my opinion is Base Venomicon. IMO this is the #1 issue with SS CAP by no small margin after the Pyroak nerf. It has almost single-handedly made teambuilding a huge headache with its checks being so few in numbers, leading to a lot of tournament squads being outright bad vs it. Whether this is due to intentional negligence – "my opponent won't bring it" – or is a slip of the mind in the builder, I can't say. For example though:
atrax madara vs baloor w1
TrickScarf Fini and Encore Astrolotl is the main Book counterplay here; the former is far from reliable for obvious reasons, and while the latter is way better than having nothing, you're still in a poor position if Venom attacks as Astro switches in. There might not be an abundance of setup opportunities with other teammates like SD camel pressuring Venom quite well, but depending on the unrevealed Melmetal and Chomp sets, it's more than possible to find good turns – having no Knock Off user also helps Book's case a lot in this matchup.
clean vs ikaishi w1
The SD camel, Air Balloon Heatran, and Taunt Tornadus-T will help a little against Venom but ultimately not enough; counterplay looks shaky at best to me, likely resorting to sacking Koko for ~70% of Venom's health and trying not to let it Roost up again for free.
tnm vs rsq w3
Another team that relies on a faster Encore user to keep Book in check, this time as a Colossoil. Being able to slow pivot Colo in with Corviknight is extremely useful and probably works long enough for you to secure an advantage, so the matchup looks playable enough; though, just the fact that this team needs to run Encore Colossoil is telling of the awkward choices Venom can force in the builder (hell, I've used Imprison Venom as an answer before), and in a more drawn out game, Encore's 8 PP may not be cutting it.
crying vs micaiah w3
Non-AV Future Sight Slowking (+2 cane 2hkos) is about all that crying can use to pressure Venom here, maybe being able to get a big Knock Off with LO Kartana early and keeping it low with rocks; probably one of the scarier Venom matchups out of the few I've listed.
potatochan vs tnm w5
This was a team I built for potatochan week 5, and unfortunately I couldn't get the concept to work while still being safe against Venom. We were pretty sure TNM wouldn't load it, though, and rolled with it anyways. Sometimes this works out, and it isn't a horrible strategy in tournament play, but you know that you're always rolling the dice by willingly sacking the matchup against one of the tier's best winconditions. Flatly though, if every team in the metagame was truly well-prepared against Venom, I think we would witness an extraordinary drop off in team diversity because of how small its pool of checks is. Way too many builds/concepts simply cannot be safe against it and either have to be scrapped or loaded with a lot of risk, and it's extremely frustrating to face that dilemma between creative freedom and being fully prepared.
atha vs snaga w4
This was also
a team I built that the Crawlers ended up using twice I believe; there's no explicit hard check to Venom here, instead relying on a combination of Encore Astro, SD camel, and Volt Koko to outplay as best as possible. As quz already said, despite the team carrying a number of mons that theoretically pressure Venom well, Venom is frighteningly good at still threatening to win the game outright. This kind of gets at the heart of the issue – Venom as a pokemon demands reactive as opposed to proactive counterplay. While you can often answer something like Venom-E by keeping up momentum and suffocating it out of the match, asking the same for base Venom is a tall order; realistically, without a dedicated answer that can reliably and repeatably switch in and force Venom out (which this team doesn't exactly have), you're in a tough position. And the number of Pokemon that can accomplish this is just too low right now.
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I'm not implying that these teams are all 6-0s waiting to happen; moreso that even in "top-level play" we see teams either purposefully or accidentally forgoing checks because of how inherently difficult it is to answer, and the suboptimal choices it can force you to make in the builder or in-game (encore on random mons, desperately sacking something like koko to force it out, etc) are often more than enough to win without a full sweep.
While Saharaja's release arguably made Venom worse, i.e. one of its most common setup opportunies (Lando) is less common & SD Raja can threaten it quite well, it's also forced some other changes that are to its benefit. Notably, Rotom-W lost almost any reason to run Nasty Plot or Thunder Wave sets; Slowking-G got worse as a whole; Astrolotl has more reason than ever to drop Encore for Wisp; Argh and offensive Grasses (huge bait) are rising in usage.
Now, Book is far from the best mon in the tier; it's still only A rank and certainly has its limits. Hurricane is a silly move that holds Venom back from real consistency, and one of its better checks in Zapdos is the strongest it's been in a long while. There are some matchups where Venom can never do anything because it's stonewalled by a healthy Zapdos/Slowking-G, is too busy fulfilling defensive duties to ever set up, gets Knocked and vortexed on, etc. (Though there are also games where you score one timely confusion on Zapdos and immediately win). But the constraint it has in the builder alone is enough to warrant action to me. Venom is in as good of a position as ever and I think time has only proven that it should have been nerfed months ago.
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