I'm honestly puzzled as to why Simple was banned.
+2 252+ SpA Fairy Aura Xerneas Moonblast vs. 252 HP / 200 SpD Primal Groudon: 201-237 (49.7 - 58.6%) -- 99.6% chance to 2HKO
This is generic, regular Ubers Xerneas (almost always) 2HKOing a Primal Groudon that has substantially invested in Special bulk with a
resisted hit. Replacing Fairy Aura with +4 means that you avoid a 4% chance of not getting the 2HKO, whoo? Not even getting into Grass Knot, which is a 2HKO on Primal Groudon at +2 even if it's
fully Specially Defensive. (At +4 Grass Knot can
never OHKO fully Specially Defensive Primal Groudon, either)
The claim that
Simple Xerneas in specific can invest in bulk is bizarre. The generic Ubers Xerneas in the calc has a whole 44 EVs invested in Speed, whoo?
+2 252+ SpA Xerneas Thunderbolt vs. 248 HP / 252+ SpD Ho-Oh: 230-272 (55.4 - 65.5%) -- guaranteed 2HKO
+4 252+ SpA Xerneas Thunderbolt vs. 248 HP / 252+ SpD Ho-Oh: 344-406 (82.8 - 97.8%) -- guaranteed 2HKO
Simple and non-Simple both 2HKO Ho-Oh, both OHKO through Stealth Rock if it's not Magic Guard (Which it usually is in AAA Ubers) when using Thunderbolt.
+2 252+ SpA Xerneas Thunderbolt vs. 252 HP / 252+ SpD Multiscale Lugia: 115-136 (27.6 - 32.6%) -- 72.3% chance to 4HKO after Leftovers recovery
+4 252+ SpA Xerneas Thunderbolt vs. 252 HP / 252+ SpD Multiscale Lugia: 172-203 (41.3 - 48.7%) -- guaranteed 3HKO after Leftovers recovery
Multiscale Lugia can actually Roost through
Simple Xerneas' Thunderbolt, or more likely it tanks one hit and Whirlwinds out Xerneas, removing its boosts and now Simple is useless. Admittedly, this is one case where Simple is
actually beneficial, because non-Simple does sufficiently low damage Lugia can potentially do something like drop Toxic and
then Roost spam, maybe even switch into Stealth Rock and Roost up, but honestly Magic Bounce Xerneas is
way more of a problem for Lugia -and can even pull off getting a
second Geomancy up in Lugia's face, directly matching Simple's boosts.
Xerneas with Simple isn't actually that much of an improvement over regular Xerneas, and Protean Xerneas has
equal offensive performance anytime it's not turning to Moon Blast -and most switch-in attempts are going to be things that Moon Blast isn't optimal against (eg Ho-oh) so Protean is barely any worse, and even has some situational advantages, such as Thunderbolting Ho-oh giving it resistance to Brave Bird. (Most Ho-oh are Magic Guard, not Gale Wings, so this even matters in actual matches)
Extreme Killer Arceus' biggest reason to run Simple is that it's a straightforward improvement to its basic set with little in the way of disadvantages or situational flaws. It's not broken.
+2 252 Atk Life Orb Tough Claws Arceus Shadow Claw vs. 248 HP / 252+ Def Giratina: 309-367 (61.4 - 72.9%) -- guaranteed 2HKO after Leftovers recovery
+4 252 Atk Life Orb Arceus Shadow Claw vs. 248 HP / 252+ Def Giratina: 356-421 (70.7 - 83.6%) -- guaranteed 2HKO after Leftovers recovery
Tough Claws at +2 and Simple reaching +4 both 2HKO Physically Defensive Giratina.
+2 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 172 HP / 0 Def Primal Kyogre: 456-538 (118.7 - 140.1%) -- guaranteed OHKO
+4 252 Atk Life Orb Arceus Extreme Speed vs. 172 HP / 0 Def Primal Kyogre: 526-620 (136.9 - 161.4%) -- guaranteed OHKO
They both OHKO somewhat bulky Primal Kyogre with Extreme Speed after one boost.
+4 252 Atk Life Orb Arceus Extreme Speed vs. 248 HP / 252+ Def Yveltal: 359-422 (78.9 - 92.7%) -- guaranteed 2HKO after Leftovers recovery
+2 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 248 HP / 252+ Def Yveltal: 309-367 (67.9 - 80.6%) -- guaranteed 2HKO after Leftovers recovery
Small advantage to Simple against non-Unaware Yveltal -it will always KO Yveltal switching into Stealth Rock, where Tough Claws has a less than 50% chance of doing so.
+4 252 Atk Life Orb Arceus Shadow Claw vs. 252 HP / 252+ Def Multiscale Lugia: 169-199 (40.6 - 47.8%) -- guaranteed 3HKO after Leftovers recovery
+4 252 Atk Life Orb Arceus Extreme Speed vs. 252 HP / 252+ Def Multiscale Lugia: 144-170 (34.6 - 40.8%) -- 61.8% chance to 3HKO after Leftovers recovery
+2 252 Atk Life Orb Tough Claws Arceus Shadow Claw vs. 252 HP / 252+ Def Multiscale Lugia: 147-173 (35.3 - 41.5%) -- 77.1% chance to 3HKO after Leftovers recovery
+2 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 252 HP / 252+ Def Multiscale Lugia: 125-148 (30 - 35.5%) -- guaranteed 4HKO after Leftovers recovery
They both break Multiscale Lugia by hitting it with Shadow Claw and then finishing with Extreme Speed -and they both are unable to break it if it just spams Roost. Admittedly Tough Claws can't consistently OHKO with Shadow Claw after Stealth Rock? Also, if Lugia is going to sit there and let them boost some more, Tough Claws is better.
+2 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 252 HP / 0 Def Xerneas: 437-515 (95.8 - 112.9%) -- 75% chance to OHKO
Tough Claws will usually OHKO Xerneas after one boost, and is obviously better at trying to revenge a Xerneas that's used Geomancy.
+2 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 252 HP / 0 Def Rayquaza: 456-538 (110.6 - 130.5%) -- guaranteed OHKO
OHKOs bulky Rayquaza, no need for Simple.
+2 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 248 HP / 0 Def Ho-Oh: 456-538 (109.8 - 129.6%) -- guaranteed OHKO
OHKOs bulky Ho-oh...
Tough Claws has mostly the same functional performance (bar using Earthquake to defeat Primal Groudon or the like, but almost all the Arceus I've seen have only run Extreme Speed and Ghost coverage) after one boost, performs better before boosting, is so close to Simple after two boosts that damage variance drowns it out
+4 252 Atk Life Orb Tough Claws Arceus Extreme Speed vs. 0 HP / 0 Def Mew: 625-737 (183.2 - 216.1%) -- guaranteed OHKO
+6 252 Atk Life Orb Arceus Extreme Speed vs. 0 HP / 0 Def Mew: 641-756 (187.9 - 221.7%) -- guaranteed OHKO
and is obviously superior with maximum boosting and against Unaware -and unlike Simple, it can't be meaningfully checked by an Ability like Unaware. (There is no "defensive Mold Breaker"-esque Ability that neuters Ability-based damage boosts -Mummy is the closest thing to such functionality)
I'm baffled as to why Simple got banned. I'd totally have understood banning Contrary while I was away if AAA Ubers is against banning
Pokemon (I really think
Rayquaza should be banned, not Contrary, but I'd understand banning Contrary if a Pokemon-inclusive ban philosophy is the intention, which would be in line with Ubers philosophy in general) but I cannot imagine why anyone would think Simple needs a ban, not on the basis of Xerneas and Arceus. Xerneas is truly and honestly
better with other Abilities, and Arceus will simply shift to Tough Claws with barely any impact on its actual performance.
We really need to look into Deoxys-a, it's protean set is absolutely terrifying to switch into. In Ubers its already A+ rank with its attrocious typing - here it has stab on absolutely everything... And it's bulk really doesn't matter, bar Deoxys-S it has the fastest Extreme Speed in the metagame. How does anything switch into this?
Deoxys-A has coverage moves from every single type with, at minimum, a 75 Base power move... Get this thing out of the tier, right away.
Eh. This is AAA
Ubers. If it's not AG-tier, my impression is bans are discouraged? Deoxys-Attack also suffers a lot if you don't specifically use it as a lead, which makes it less of an issue that switch-ins to it are hard to find -you just need a good counter-lead to make it a lot less appealing.