Moving on from that tangent we have the Normal typing which is always welcome, providing the always welcome ghost immunity with the punishing downside of being vulnerable to another common type in the tier. Scizor being the most notable of the few that can reliably revenge kill Blursa while switching into it's powerful Blood Moon.
A few other notable switch ins to Blood Moon(And wont immediately suffer a follow-up earth power): Chansey (OU Defensive)(27.7%), Blissey (OU Defensive)(27.3%), Ting-Lu (OU Defensive Hazard Setter)(36.9%), Slowking-Galar (OU Assault Vest)(43.6%), Corviknight (OU Physically Defensive)(43.1%), Alomomola (OU Assault Vest)(48.7%), Dragonite (OU Choice Band/OU Swords Dance)(47%), Dragonite (OU Bulky Attacker)(39.3%), Ogerpon-Cornerstone (UU All-Out Attacker/UU Swords Dance)(51.8%), Ogerpon-Cornerstone (OU Swords Dance)(52.1%), Slowking-Galar (OU Defensive Pivot)(52.7%), Primarina (OU Assault Vest)(56%), Toxapex (OU The Pex (Defensive))(56.7%), Hatterene (OU Assault Vest)(56.6%), Tornadus-Therian (UU Pivot)(57.1%)
Of the pokemon listed here, only Ting-Lu is actually a splashable check to BUrsa. Galarian Slowking usage is significantly down due to the presence of Kingambit and MTtar with their pursuit to trap it super easily, which is why you're especially not using AV which is so vulnerable to it. Not to mention it does nothing to actually beat CM BUrsa. Corviknight is only a check if it runs Body Press AND Iron Defense, as otherwise BUrsa will just tank Body Presses with lefties+Moonlight until it's boosted enough to break through Corv (which it does at +4 btw, not hard to do in that match up if Corv lacks ID). Chansey and Blissey are not common or splashable pokemon, being very difficult to fit outside of stall. Dragonite fails to be a check at all if Multiscale is broken, as +1 Bloodmoon will OHKO it (unless you're bulky DNite but that fails to threaten BUrsa at all so it'll just boost and break through it). Ogerpon-C is an offensive check and doesn't fit on the defensive teams (this is relevant to why BUrsa is banned). Primarina can only switch in
one time as Bloodmoon does over 40% to it and with hazards up, that is too much. Toxapex just gets folded by +1 EP unless max special defense (and does nothing back to it outside Toxic which is nowhere near fast acting enough to stop BUrsa from taking multiple KOs vs the defensive teams Pex is on). Hatterene is both a very mediocre pick but also is slower and complete set up fodder for CM. And TornT cannot touch it outside Knock Off and dies in the process to +1 Bloodmoon. And Alomomola I don't think I need to mention why it's not a check between getting flattened by CM and needing AV which prevents it from doing anything to BM (it's not breaking through it and without Toxic, cannot stop its sweep at all).
Also I'll touch on it, but MScizor is only able to revenge kill with offensive sets running Close Combat, which you don't really see on slower defensive teams because of the lack of defense investment on those sets and their lack of Roost for longevity.
So we've established a lack of splashable defensive counterplay beyond 1-2 pokemon (and one of those requires very specific sets).
252 Spee Primarina(219), 0 Spee Landorous-T(218), 252 Spee Azumarill/Iron Hands(218), 0 Spee Great Tusk(210), 0 Spee Rillaboom/Kommo-o(206), 40 Spee Heatran(200), 0 Spee Mamoswine(196), 0 Spee Skarmory(176), 20 Spee Scizor(171), 0 Spee Corviknight(170), 0 Spee Pelipper/Alomola(166)
This barrier of speed while costly for BlUrsa's stat investment allows them a certain advantage in some of them matchups most notably those of Primarina and Landorous-T.
Mentioning its speed is really irrelevant because it's a bulky wincon. It outpaces the walls its meant to break down. LandoT also cannot beat BUrsa, Iron Hands is rare and outsped with minor speed investment, Great Tusk needs Fighting Stab to beat BUrsa (not an easy fit since it wants Ground Stab, Spin and Ice Spinner). Rillaboom is terrible, Kommo-O is rare, Heatran loses to CM BUrsa, Mamo is nonexistent, Skarmory is almost nonexistent, MScizor loses to BUrsa without CC (which defensive cannot run), Corv loses without ID+BP, Pelipper is rain exclusive and Mola loses in general.
My main issue is you're just listing off pokemon without factoring their relevance or usage in the tier, if they're good at all, and without factoring in other things. You just list random mons that aren't used like Bisharp(?), Mimikyu(?), Arcanine-Hisui? Like you don't have to dig into bad mons to illustrate its power. Use OU pokemon for that. Also BUrsa does not need coverage in most cases as Bloodmoon+EP alone is enough to break down defensive teams with CM boosts.
BlUrsa feels like its in a weird spot in terms of strategy. On one hand it's an incredible powerful out of the gate attacker much like Char Y, though it misses out any kind of team support outside of yawn/taunt although that will severely hamper BlUrsa's ability to sweep without Calm Mind and weakens BlUrsa even more against the stall teams that will give BlUrsa a hard time hazing away stat boosts, threatening toxic/para and forcing constant switches that combined with knock off will wear BlUrsa down.
BlUrsa's biggest problem on paper is the 50/50 nature of the game you play with your opponent. Whether it be a protect, pivot, sub, or nothing at all there's plenty of mind games to play around Blood Moon and how you use it or don't. This struggle to predict combined with the sluggish nature of BlUrsa encourages the use of pivot moves to get it in safely or, ideally, trick room into teleport to allow BlUrsa multiple turns of terror. However, dedicating so much of your team to a strategy that last 4 turns while giving your opponents ample time to buff/stack hazards or anything they want is hardly an ideal strategy. Most of the time BlUrsa would serve as a punishment to Landorous-T leading players or an opportunity(with bulk investment instead of speed) to counter a late game kingambit and whatever else might still be around. Otherwise most of your games will boil down to hoping your opponent failed to bring a sufficient special wall.
Bloodmoon is not difficult to use at all. Simple CM+2 Attacks (Bloodmoon+Earth Power) is a easy to use and highly effective set that flattens defensive teams. Balance struggles to stop it from getting a bunch of kills duo to their weaker nature and it feasting on their defensive backbones while Bulky Offense it still can go for multiple KOs since they feature similar defensive pokemon that Balance can run, that BUrsa feast on and it's extremely difficult to pivot around without risking damage. Is it boosting and you switch to an offensive threat to pressure it out? Oops it just attacked and dropped your offensive mon. It needs minor support for positioning but slow pivots (and pivots in general) are abundant in this tier and it's not difficult to position.
Look, I get that a lot of pokemon get chucked up to the Ubers tier just for the sake of not having them run rampant before they can be properly investigated but give the big red bear a break. It was clearly a mon that was not designed with singles in play and without a sufficient amount of support such as max hazards + trick room its not getting more than a single kill against a competently played team.
CLOSING STATEMENTS
This entire post was just a way to hopefully put some attention on the big ol' bear. Give it some love, and while I doubt it'll ever find much of a niche in the hyper competitive tier of Uber's I could easily see it as a strong late game threat in NatDex OU, or maybe even a setup sweeper should someone manage to get the trick room off without sacking too much.
This confuses me but I assume you weren't around when it was legal before so you just weren't aware of what it was like before.. BUrsa isn't some "we just chucked it in Ubers by default" mon. It was allowed in OU for some time earlier in the gen, but ultimately it was way too oppressive to deal with and was canned. It absolutely functions well in singles just as it does in doubles. There's a reason why when it was suspected in regular SV OU it was banned with a 93% majority, a level of one sided you almost never see in suspects. It had no issues getting multiple kills when it was legal, and while it would need a bit more finesse to do so now without Tera, it would still be a very negative presence in the tier that suffocates defense while still being able to trade into offense (which is frailer and thus not necessitating boosts).
For me, BUrsa is a mon I sincerely hope we never free for the remainder of this generation.
