Have done some laddering in new meta with a highly dubious team but worked out pretty well. Some observations/notes/speculations on how the Mega Diancie ban affects most mons on the VR. Posting this here instead of Resources because its not formal VR noms or anything.
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Winners - Mega Diancie is somewhat unique in that its departure is favourable for a good majority of the mons in the meta due to how potent it was against both offensive and defensive mons. In particular, due to this it is actually not very certain how the meta will shape out and adapt because almost everything gets better.













(Literally like 95+% of offensive mons)
All of these benefit directly from Diancie's ban by losing a revenge-killer from Extreme Speed and/or just outspeeding and nuking with Boomburst. In particular:
Stuff like

can now choose to forgo Psysurge,



can setup easier on more passive mons,


are also the next best options to fill in the void of strong Fairy attackers, the former boasting an even stronger Specs Boomburst while the latter does mixed sets and capitalizes on Poisonceus's anticipated drop.


















(Basically every non Diancie-check)
Defensive mons can benefit in a variety of ways. Some Def non-resists like

no longer have to deal with letting Diancie in and being forced out, the Dragons lose a soft check, a lot of the less bulkier mons no longer get 2HKOed by Specs Boomburst (or for


, Mixed ESpeed). The two Arceus formes are listed because they have a worse matchup than the other formes due to being neutral to everything and not hitting Diancie super effectively.
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Neutral - These are some mons that are either Diancie soft-checks that can retain usability post ban by either switching roles or just keeping their role and not have to worry about being an insufficient Diancie check, or some offensive mons that do not have a poor MU into Diancie.








remains a potent Scales Arc by virtue of typing.

will likely stop using Scales but FC is useable.

Steels remain steels, notable in able to forgo Fire-immune if unnecessary.

can preserve a niche with Sunsteel resistance and Psychic-type
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Losers - These lose a lot of defensive purpose since their main purpose was to check Diancie (while checking some other stuff) but with Diancie gone why not just use something that checks the other stuff stronger.

There is like basically no point in using this, Fire isn't that good defensively against stuff like


and

provides the Psychic typing against threats like

.

Was almost exclusively used for Diancie lol. Typing no longer is very useful and compromises Ground and Psychic matchups.


Also Poison-types. They can technically do sapblocking stuff but both are pretty outclassed in that regard and have annoying weaknesses to cover for.
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Think the meta would be quite volatile for a while with a lot more freedom both offensively and defensively, especially with the considerable diversity for both. Basically all the defensive options remain strong with decent variety in sets. Offensively we have stuff like


as SpA,


as Atk,


as mixed, and a bunch of bulky setup stuff like


. Should be a very interesting meta for innovation and adaptation, especially with 2 more rounds of Ghosting, some rounds of Majors, and eventually Open in a month to test how the meta developed. (Afterwards we can maybe retest some stuff due for a retesting).
However, Ooze is still an enormous problem. While sapblocking in general lost one of its more potent enablers, threats like

still are potent and with Ooze around can force the same sap mindgames as always. As I mentioned before, sapblocking is going to be a part of this generation simply due to how PP works and I think that stuff like Bounce/stat-based sapblocking is reasonably healthy, in particular you can build and situationally play around them. Meanwhile, Ooze simply doesn't give leeway in playing around and is overall an unhealthy and unbeneficial aspect of the meta. I also have seen substantial support for Ooze ban in discussions on cord while I have seen basically no constructive defense (if anyone has any please do share it here or on cord and ping).
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Also can we like please stop with Imposter this Imposter that it gets quite repetitive when for the nth time someone brings it up and half a page is filled with stuff relating to it that goes nowhere for the nth time and it just ends up being clutter. Imposter certainly can be argued as the strongest it has been in a while in a meta with no PH and good trapping but even still it has reasonable counterplay options. The only remotely problematic aspect would be that Imposter encourages Sap which has a myriad of problems the main one starting with L ending with E but that obviously is problematic on its own. Also Imposter overused should be like no surprise at this point it has a comfortably positive winrate in like every tournament since 2019 its good splashable and thus people run it on most teams, just like how many metas have a dominant mon that warps the tier around it but not in a completely unhealthy way because you have multiple possible outs.