Reuniclus

Reuniclus is one of the best Pokemon in the tier as a result of its amazing ability, good offensive prowess, and defensive profile. Magic Guard invalidates the passive damage bulkier threats like Ferrothorn, Slowking, Rotom-W, Tentacruel, Skarmory, and Gliscor rely on, including sandstorm, entry hazards, and status, giving Reuniclus a great matchup against their team structures, especially when accompanied by Spikes. Its great coverage moves like Focus Blast, Hidden Power Ice, and Thunder make it just as scary to offensive threats switching in as the defensive ones it sets up on. For general defensive purposes, it can switch into and force out popular threats like Gliscor, Terrakion, Garchomp, Tentacruel, Ferrothorn, defensive Heatran, and Alakazam lacking Signal Beam or Shadow Ball. It also has good set versatility; on top of Calm Mind, it can run a powerful 3 attacks set that immediately threatens bulkier teams and a Trick Room set that flips the script on faster offensive teams. However, very strong Pokemon like Keldeo, Excadrill, Latios, Kyurem-B, and offensive Heatran can overwhelm Reuniclus as a result of its low Speed and lack of resistances. Pokemon that can prevent Reuniclus from setting up safely like Trick Choice Scarf Latios, Perish Song Celebi and Politoed, and Encore Alakazam and Politoed can punish the Calm Mind set. Reuniclus is also very vulnerable to Pursuit from the omnipresent Tyranitar, which often runs Chople Berry to take Focus Blast, as well as Scizor. Its Calm Mind set loses to Jirachi and can get walled by common Pokemon depending on coverage, like Excadrill if lacking Focus Blast and Dragonite and Latios if lacking Hidden Power Ice.