Finally made reqs today, I'll be voting
ban. While Ubers has always had Pokemon that can cause absolute chaos if they can come in safely, many of them are held back by bad defensive typing (Calrex-Ice), low Speed (Kyogre) or low bulk (Calyrex-Shadow). Zacian-C has none of these problems - it's one of the fastest Pokemon in the tier, it has great bulk and Steel / Fairy is one of the best defensive typings out there. Those factors mean it has no shortage of Pokemon it can come in on safely like defensive Yveltal, Xerneas and Eternatus in Rain and start smashing things up. Counters? Quagsire does wall it, but as others have said it's basically useless outside this and funnily enough most players don't like playing 5 vs 6. Groudon? Yeah you'd better be running max defense, otherwise...
+1 252 Atk Zacian-Crowned Behemoth Blade vs. 252 HP / 0 Def Groudon: 223-264 (55.1 - 65.3%) -- guaranteed 2HKO after Leftovers recovery
+1 252 Atk Zacian-Crowned Play Rough vs. 252 HP / 0 Def Groudon: 202-238 (50 - 58.9%) -- 73.4% chance to 2HKO after Leftovers recovery
And even if you are running max physical defense, it needs to be in pristine shape, and you'd better hope it's not running an Adamant nature
+1 252+ Atk Zacian-Crowned Behemoth Blade vs. 252 HP / 252+ Def Groudon: 186-220 (46 - 54.4%) -- 55.9% chance to 2HKO after Stealth Rock and Leftovers recovery
Physically defensive Necrozma-DM? Much like Quagsire it's not much particularly outside of dealing with Zacian-C, as it lets other dangerous sweepers like Dragon Dance Zygarde, Rock Polish Groudon and, if it doesn't run Earthquake, Dragon Dance Zekrom come in for free and set up. Even then, it only reliably beats the all out attacker set - if Zacian Swords Dances on the switch, Necrozma gets 2HKOed by a +2 Close Combat, and isn't even guaranteed to OHKO a full health Zacian with Earthquake at -1 Def. Oh, and if Stealth Rock is up AoA sets with Assurance can still beat non Heavy-Duty Boots Necrozma with good roles:
+1 252 Atk Zacian-Crowned Assurance (120 BP) vs. 252 HP / 252+ Def Prism Armor Necrozma-Dusk-Mane: 219-258 (55 - 64.8%) -- guaranteed 2HKO after Stealth Rock
+1 252 Atk Zacian-Crowned Close Combat vs. 252 HP / 252+ Def Necrozma-Dusk-Mane: 146-172 (36.6 - 43.2%) -- guaranteed 3HKO after Stealth Rock
+3 252 Atk Zacian-Crowned Close Combat vs. 252 HP / 252+ Def Necrozma-Dusk-Mane: 243-286 (61 - 71.8%) -- guaranteed 2HKO
0 Atk Necrozma-Dusk-Mane Sunsteel Strike vs. -1 0 HP / 4 Def Zacian-Crowned: 211-250 (64.9 - 76.9%) -- guaranteed 2HKO
0 Atk Necrozma-Dusk-Mane Earthquake vs. -1 0 HP / 4 Def Zacian-Crowned: 282-334 (86.7 - 102.7%) -- 18.8% chance to OHKO
Defensive Ho-Oh might seem like an answer, but Jolly can 2HKO with Behemoth Blade into Wild Charge with some good roles (Adamant is guaranteed to 2HKO). Oh and without sun uninvested Sacred Fire doesn't OHKO, so you'd better hope for a burn.
+1 252 Atk Zacian-Crowned Behemoth Blade vs. 248 HP / 208+ Def Ho-Oh: 120-142 (28.9 - 34.2%) -- 3.7% chance to 3HKO
+1 252 Atk Zacian-Crowned Wild Charge vs. 248 HP / 208+ Def Ho-Oh: 290-342 (69.8 - 82.4%) -- guaranteed 2HKO
0 Atk Ho-Oh Sacred Fire vs. 0 HP / 4 Def Zacian-Crowned: 240-284 (73.8 - 87.3%) -- guaranteed 2HKO
So to sum up, it has only 1 counter that sucks at everything else, 2 good checks that need to in pristine health to reliably handle it and...nothing else. Unless you have one of a very small pool of Pokemon to check it, it will claim a KO every time it comes in. This has made the meta extremely repetitive and honestly not fun to play IMO, it's even worse than in ORAS and USUM when almost every team had Primal Groudon.
As a side note, this is the team that I used to get reqs. Don't sleep on CroGre, it's a great late game bulky sweeper.
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