Competitive Pokémon History - Arceus-Rock Quiz

Answer: Ho-Oh

Ho-Oh would be felled with a single, 4x super effective, Judgment, while Arceus-Rock's resistances to both of Ho-Oh's STAB offered it leeway to switch straight into it. No other Arceus forme could make that claim. Even Water and Electric variants, with the typing advantage on Ho-Oh, struggled to actually defeat it one on one due to its massive Special Defense.

Answer: Scizor

Scizor can come in on any Arceus-Rock set, be it Calm Mind or Swords Dance and, even after Arceus-Rock boosts once, Scizor's strong super effective Bullet Punches will outdamage it.

Other Pokémon who could counter Arceus-Rock were Palkia, Dialga, Kyogre, Arceus-Fighting, Arceus-Steel, and Arceus-Ground. This was mainly due to typing advantages. Groudon, however, cannot consistently counter Arceus-Ground, as Calm Mind variants will be able to OHKO it after a single boost with Grass Knot. Groudon did make for a usable check, however.

Answer: Five

Rock has been weak to Fighting, Grass, Ground, Steel and Water. Steel walls it defensively, and uniquely can deal with it offensively, giving Rock an even worse matchup against a traditionally great defensive typing. Meanwhile, Kyogre has long been a staple Water type, smashing Arceus-Rock like nothing. Groudon (and later, it's Primal forme) and Arceus-Ground headline Ground types which have traditionally handled Arceus-Rock well, while Fighting and Grass have had a number of major figures over the years as well. Simply put, this has been quite challenging for it to deal with.

Answer: Their presence makes Arceus-Rock even bulkier than it already is

Both Tyranitar and Hippowdon have the Sand Stream ability. Until the end of the fifth generation, this ability summoned a permanent sandstorm. Even when it only become temporary afterward, all Rock types receive a 1.5x boost to their Special Defense when under the effects of a sandstorm.

This mitigated Arceus-Rock's poor defensive typing and gave it the upper hand in many Calm Mind wars due to the added Special Defense from said sand.

Answer: Limited coverage movepool

It's typing was perfectly fine, as Rock is not offensively immune against anything. It's stats are also clearly the exact same either way, leaving the inferior coverage movepool as the correct choice. Calm Mind sets start off with Calm Mind/Judgment/Recover, then have an abundance of options afterward. Fire Blast, Flamethrower, Thunder, Grass Knot, Ice Beam and Focus Blast are all perfectly usable. If none of them tickled the player's fancy and they preferred a great matchup against stall, Refresh was usable. Swords Dance sets are practically required to run Earthquake for coverage with no usable coverage moves thereafter.

They are therefore stone walled by just about anything resistant to Rock that is not weak to Ground, such as Groudon, Skarmory, and most Steel types in general that the Calm Mind set can overcome.

Answer: Bird Antidote

An entire team's issues with Flying types could be remedied by simply slapping Arceus-Rock onto a team if desired. Ho-Oh would be crushed by any of Arceus-Rock's STAB moves, while other premiere Flying types, such as Yveltal, Mega Salamence and Rayquaza, failed to be able to deal with Arceus-Rock as well, even if packing super effective coverage for it.

While Arceus-Rock had plenty of exploitable weaknesses, if the trainer could account for them, it's niche of dealing with Flying types was highly valuable and worth the effort of making the arrangement work.

Answer: It limited its otherwise easy counterplay

Ground, Fighting and Steel types could deal with Arceus-a Rock laughably easily. Fortunately, the vast majority of them would be heavily crippled should Arceus-Rock be able to burn them with Will-o-Wisp, deterring them somewhat from brainlessly switching into it. Without Will-o-Wisp, Arceus-Rock would have an entire phonebook worth of Pokémon who could hard counter it.

As such, it became basically mandatory for any of its sets to equip.

Answer: Primal Kyogre

Mega Gengar actually comes close despite its frailty, as it can blast Arceus-Rock to pieces with a couple of a Focus Blasts, use the Taunt/Disable/Perish Song set to reliably remove it, and can stop it from switching out with its ability Shadow Tag. Primal Kyogre can easily counter Arceus-Rock, with its mighty Special Defense only being eclipsed by its astronomical Special Attack, taking Judgments with ease, not being bothered much by Will-o-Wisp, and slamming Arceus-Rock for an OHKO with Origin Pulse even if Arceus-Rock had previously boosted with two Calm Minds. Thus, it was impossible for Arceus-Rock to make any serious progress if the opponent had a healthy Primal Kyogre on their team.

Answer: Large amounts of new checks/counters

Marshadow, Necrozma-DuskMane, Lunala, Solgaleo, Magearna, and Zygarde-C are examples of checks and/or counters, many of which became prominent faces in the meta game that could thwart Arceus-Rock easily. This cut into its viability quite a lot.

Answer: Yes

Being able to maintain Stealth Rock against many Uber threats and check/counter practically every Flying type in the game still gave Arceus-Rock a small niche. It faced competition as a Stealth Rocker, as its Fairy and Ground type counterparts were better at setting and maintaining the hazard, so it was only worth selecting if the team needed an answer to Flying types somewhere.