Common Roles

Defensive Wall: Articuno has good special bulk as well as reliable recovery, allowing it to perform the role of a special wall quite effectively as long as the Pokemon it is trying to check do not have ways to hit its crippling weaknesses. It can also effectively prevent setup due to having access to both Haze and Roar as well as acting as a solid pivot with U-turn. While it does have a lower Defense stat, it is also able to check physical attackers in a pinch due to its good natural bulk as long as they don't have Rock-type coverage.

Late-game Cleaner: With Agility, an offensive Articuno set can be used as a late-game cleaner once the opposing team is weakened enough. However, this set is heavily reliant on both support from its teammates and Terastallization, as Articuno has near nonexistent coverage moves and its Special Attack is average at best, often requiring a damage-boosting item to do any notable damage.

Common Moves

Primary STAB Moves: Ice Beam, Freeze-Dry, Hurricane, Air Slash, Brave Bird, Triple Axel, Ice Shard

Setup Moves: Agility

Utility Moves: Roost, U-turn, Haze, Roar, Reflect, Light Screen, Tailwind, Feather Dance, Ice Spinner

Coverage: Tera Blast, Water Pulse, Ancient Power

Niche Moves

Icy Wind: Icy Wind can be used as a form of speed control against a threatening Pokemon, and it can allow Articuno to get an extra attack off against its opponent.

Weather Ball: When paired with weather-setting teammates, Weather Ball can be used to give Articuno much-needed coverage.

Weather-changing Moves: Articuno has access to all four weather-changing moves, allowing it to potentially be used to disrupt opposing weather strategies and enable its teammates.

Common Items

Heavy-Duty Boots: Articuno is a defensive Pokemon with a double weakness to Stealth Rock. This fact makes Heavy-Duty Boots effectively mandatory on sets other than late-game cleaners and ones that use Tera to change its typing.

Niche Items

Leftovers: In situations where you are going to use Tera on Articuno or when the opponent somehow doesn't have a Pokemon that can set Stealth Rock, Leftovers can be a superior choice to Heavy-Duty Boots in order to give Articuno more longevity.

Resistance Berries: If Articuno is able to avoid damage from Stealth Rock, a Resistance Berry can be used to help it check a threatening attacker.

Damage-boosting Items: Offensive Articuno sets need all the help they can get in order to perform their job well. Items that boost one of its STAB attacks and generic damage-boosting items such as Life Orb can be used to give it the push it needs to be a more effective late-game cleaner.

Weakness Policy: Alongside Agility and Tera, Weakness Policy can be used to make Articuno a much more threatening cleaner, using its natural bulk to survive a hit and activate Weakness Policy.

Light Clay: Light Clay can be used for more offensive strategies that utilize Articuno as a lead to set up dual screens and then attack or pivot to a teammate.

Tera

As a cheap, low-tier Pokemon, Articuno should rarely be considered for one of your Tera Captains. However, if paired with a very high-cost Tera Captain, Articuno can be a good choice for your secondary Tera Captain. It greatly benefits from Tera changing its awful defensive typing into a much better one such as Tera Water, Fairy, and Steel, allowing it to be much more effective at checking different threats. Tera Water in particular also gives it access to near-unresisted STAB coverage by using Freeze Dry alongside Tera Blast Water, being very helpful for both defensive and offensive sets alike. Offensive Articuno sets also benefit greatly from Tera, as it has effectively no natural coverage, and it can use Tera types such as Tera Ground and Fire to greatly support its natural Ice-type moves.

Draft Strategy

As an extremely low-tier Pokemon, you should not build your draft around Articuno. Instead it should be used to assist in filling in gaps and deal with specific weaknesses for your draft. With that in mind, these are some things that you should have in your draft in order to be able to make the most out of Articuno:

Wallbreakers: Articuno can support wallbreakers by taking hits for them and by pivoting to them with a slow U-turn. Pokemon such as Iron Valiant, Raging Bolt, and Garchomp have good synergy with Articuno, as it is able to take most hits that would be aimed at them.

Entry Hazard Control: Having reliable entry hazard removal is already vital for most drafts, but it is nearly mandatory if you plan on using anything but Heavy-Duty Boots on Articuno. Pokemon such as Great Tusk, Iron Treads, and Blastoise can fulfill this role and take on most or all of Articuno's weaknesses.

Entry Hazard Setters: Having good entry hazard support is essential if you want to try using Articuno as a late-game cleaner. Entry hazards also allow Articuno to use Roar as a way to spread chip damage on the opposing team. Pokemon such as Hisuian Samurott, Ting-Lu, and Iron Treads are effective hazard setters that can fit into most drafts.

Physically Defensive Pokemon: While Articuno can check several special attackers, many physical attackers can easily break past it with their coverage moves. Having Pokemon that can reliably check physical attackers such as Great Tusk, Landorus-T and Scream Tail makes it much less of a hassle to bring Articuno to a game.

Checks and Counters

Rock-type Coverage: Rock-type coverage moves are surprisingly common on a lot of Pokemon, even on special attackers, though many of them often prefer not to run them. If Pokemon such as Kyurem, Greninja, and Darkrai have a free moveslot, they can fit these moves and easily get rid of an Articuno that was meant to try and check them.

Steel-type Pokemon: Articuno has no natural way to deal any reliable damage to most Steel-types, and most Steel-type Pokemon are also able to hit it for massive damage with strong physical attacks. In most cases, pivoting out with U-turn is the best thing Articuno is able to do against these Pokemon.

Knock Off: If Articuno loses its Heavy-Duty Boots, it is suddenly taking massive damage every time it switches into Stealth Rock, effectively nullifying any defensive potential it might have.

Strong Physical Attackers: Articuno is generally built to check special attackers, so it is usually vulnerable to strong physical wallbreakers such as Palafin, Urshifu-S, and Sneasler that can break through it even without super effective coverage.