Ariados's access to Agility, a high Attack stat, and Swarm makes it a scary mid- or late-game sweeper. Ariados functions similarly to Beedrill, another Agility sweeper, but it offers better bulk, greater initial power in Signal Beam, and access to alternative Hidden Power options besides Hidden Power Bug. Agility allows Ariados to beat would-be faster foes like Abra, Anorith, Ponyta, and Quilava. Sludge Bomb is Ariados's strongest STAB move, threatening Fire-types, Tropius, and Noctowl. Signal Beam hits like a truck when Swarm is active, when it can 2HKO defensive options like Rhyhorn, Delcatty, and Porygon and OHKO threats like Anorith and Mightyena. Hidden Power Flying hits other Bug- and Grass-types such as opposing Ariados, Dustox, Gloom, and Volbeat for big damage. Substitute is vital if opting for Liechi Berry, as it enables Ariados to reliably activate its Liechi Berry, and it additionally blocks status and Intimidate and protects it from priority attackers. Psychic is another strong alternative to consider, as it allows Ariados to threaten Koffing. Leftovers is preferred for the recovery it provides and for allowing Ariados to set up Substitute multiple times. Liechi Berry can be an excellent tool for more offensive teams thanks to its sweeping potential by enabling Ariados to 2HKO common Bug-resistant foes like Corsola and Rhyhorn with Signal Beam, and it has great synergy with Swarm and Substitute. The EV spread allows Ariados to outspeed the entire unboosted metagame after using Agility. The rest of Ariados's EVs are funneled into its bulk, with the HP to let it activate its Liechi Berry at 25% health.
Ariados fits well on balance and offensive teams that could use a hard-hitting bulky attacker that defensively answers Gloom and Tropius. With a Liechi Berry, Ariados can even function as a wincon on offense and hyper offense. Ariados appreciates special attackers like Abra, Flaaffy, and Quilava, as they can deal with its checks, such as Koffing, Corsola, and defensive Ariados. When not behind a Substitute, Ariados is defenseless in the face of Fire-types like Ponyta and Quilava, which makes bulky Water-types like Seaking and Wartortle very valuable allies. While Doduo can't switch in safely against Ariados due to its fragility and tendency to wear itself down with recoil damage, having a switch-in to it is a great option to preserve Ariados's HP when it's not Agility boosted or behind Substitute. For this reason, physically bulky Rock-types like Corsola, Onix, and Rhyhorn can make for great partners for Ariados. Ariados's Rock weakness demands strong defensive checks to Rock-types, which gives the aforementioned physically defensive Pokemon great defensive value when paired with Ariados. Similarly, Mightyena can serve to soften the blows from physical attackers with Intimidate, and it can also combat Abra and other Psychic-types. Ariados's ability to break down special walls opens the door to many strong special attackers like Abra and Quilava, since they get stopped in their tracks by Delcatty, Drowzee, and Noctowl. In that same vein, Ariados is strong against Mightyena, which can open the door to physical and mixed attackers like Aipom and Ponyta that prefer not being debuffed by Intimidate.