Magearna

With a great defensive and offensive typing, solid base stats, and a handful of moves to take advantage of, Magearna is widely considered one of the most versatile threats M&M. Its Fairy / Steel typing enables it to check a wide arrange of offensive threats in the tier, with the most notable being Tapu Lele, Kartana, and opposing Magearna. Adding onto this, the additional bulk and useful abilities that Mega Stones such as Manectite and Pinsirite provide enable Magearna to check a wider array of threats such as Arceus-Ground, Terrakion, Zeraora, and Altarianite Zygarde. Its supportive movepool is also noteworthy, where moves such as Pain Split and Volt Switch enable it to sustain its health while wearing down checks and grabbing momentum easily. Access to Shift Gear and a powerful Physical move such as Return combined with the lack of solid Flying-resistant Pokemon in M&M also enables Magearna to employ a setup Shift Gear set in combination with Pinsirite, further enhancing its versatility as an offensive threat. It's especially potent as a setup sweeper because of its resistance to Extreme Speed from Pokemon like Pinsirite and Altarianite Entei, which are some of the main revenge killing options in the metagame. This versatility also makes Magearna very hard to consistently check; its checks vary greatly on the set it is running. For example, Arceus-Ground can check Manectite Magearna but will struggle greatly against Pinsirite Magearna. However, supportive Magearna sets can be stopped cold by the omnipresent Primal Groudon, which not only resists both its STAB moves but also can prevent it from pivoting by blocking its use of Volt Switch. Beyond that, Magearna can also be pressured very heavily by various other Pokemon such as Necrozma-DM, Lucarionite Terrakion, and Lucarionite Zygarde, necessitating additional support from its team to properly account for these threats. It's also worth noting that the lack of reliable recovery can also hamper Magearna's ability to stay healthy throughout the course of a match; Pain Split can be taken advantage of by the foe to recover their own health, making it an unreliable move.