Other Options

Articuno’s barren movepool leaves it with very few other options to choose from. Sky Attack is a decent option, being Articuno’s only Flying-type STAB move and very powerful in its own right. It can be used over Articuno’s Normal-type coverage, dealing huge damage to Chansey and more damage to Mewtwo. However, its two-turn nature makes it less reliable and harder to use than other moves, and Blizzard does more damage to Mewtwo over two turns. Another option is Ice Beam to save precious Blizzard PP in certain situations. Alongside Rest, it can be used to fish for a freeze, with about an 85% chance to get one with all of its PP used. However, Ice Beam Articuno is completely walled by Jynx and Chansey, since it must drop its Normal-type coverage.

Articuno can also utilize Reflect, alongside Rest, to become a good tank that easily staves off hits from Tauros, Mew, and Snorlax. Reflect Articuno's main goal is to freeze a foe, so it should run Ice Beam to maximize that chance. If Articuno uses Reflect, it will likely forgo Agility. This means that, while not completely ruined by paralysis, Reflect Articuno is threatened more by it, since it is forced to use Rest and switch out to negate the Speed drop.

Checks and Counters

Ice-resistant Pokemon: Cloyster completely walls Articuno, since it is 4x resistant to Ice, can't be frozen, and has huge Defense to make Hyper Beam deal next to no damage. Similarly, Lapras takes almost zero damage from Blizzard, can't be frozen, and threatens Articuno with Thunderbolt; however, it must watch out for Hyper Beam if it's at low health. Slowbro can easily set up Amnesia on Articuno but fears a stray freeze or critical hits from Blizzard. Starmie can hit Articuno hard with Thunderbolt and heal from Blizzard damage with Recover, but it too must be wary of a freeze.

Chansey: While Chansey must be somewhat healthy to switch in on Articuno carrying Hyper Beam, it takes relatively little damage from Blizzard and can scare Articuno away with Thunderbolt or Thunder Wave + Seismic Toss. However, Chansey must be cautious to not be frozen in the process. Although rare, Articuno can use Sky Attack on a predicted switch to do massive damage the next turn; however, Chansey will likely just heal the damage off.

Jolteon and Zapdos: Jolteon outspeeds Articuno and will almost always 2HKO with Thunderbolt. Articuno also barely misses the 2HKO with Blizzard, meaning it needs a critical hit or a freeze to win one-on-one. Zapdos, albeit weak to Ice, outspeeds Articuno and threatens to 2HKO it with Thunderbolt while narrowly surviving one Blizzard. Jolteon and Zapdos can also paralyze an Agility-boosted Articuno with Thunder Wave to negate its Speed boost.

Mewtwo: None of Articuno’s attacks hit Mewtwo very hard after it has used Amnesia, except a critical hit Blizzard, and Mewtwo has Recover to heal off any damage it does take. Even unorthodox Mewtwo sets can take at least two Blizzards, allowing Mewtwo to use Thunder Wave on Articuno followed by heavy-hitting moves like Psychic, Thunderbolt, and Self-Destruct.

Explosion: Mew, Gengar, and Snorlax, among others, can finish off a weakened Articuno with their powerful Explosions even after Articuno has set up with Agility. However, an Articuno using Reflect does not fear them.