Rayquaza

Mega Rayquaza is a powerful Pokemon in the metagame thanks to its monstrous offensive stats, high Speed that lets it outrun the crowded base 90 Speed tier, and excellent movepool, which make it strong against a majority of the format. Unlike other Mega Evolutions, Mega Rayquaza has a lot of flexibility with its movesets, leaving opponents guessing about its set and item and making it well worth the Restricted slot. It has a good offensive typing, commonly utilizing Dragon Ascent to threaten a majority of the format for neutral or super effective damage, such as Primal Groudon, Amoonguss, and Incineroar, which are generally slow and cannot threaten -1 Mega Rayquaza back for much damage barring a Dragon Claw from Groudon. Mega Rayquaza can also utilize coverage moves like Earth Power, Crunch, Waterfall, and Draco Meteor, which allows it to threaten super effective damage onto a multitude of Pokemon that it would otherwise hit neutrally such as Primal Groudon, Lunala, and Mega Salamence. Mega Rayquaza's diverse toolkit also allows it to play a supportive role thanks to the likes of Icy Wind and Tailwind in addition to its ability to nullify the effects of weather via Air Lock before Mega Evolving. Despite its overwhelming BST and diverse movepool, Mega Rayquaza can struggle against Pokemon like Incineroar and Salamence if it doesn't have the proper coverage moves or Swords Dance to counteract repeated Attack drops from Intimidate. It is also threatened by the format's offensive Fairy-types such as Xerneas, Tapu Koko, and Tapu Lele, as well as surprise tech options like Dragon Claw or Hidden Power Ice on Primal Groudon, depending on its moveset, or Ice Beam on Lunala. Mega Rayquaza is still relatively frail in comparison to other Restricted Pokemon as well and, in combination with the stat drops from Dragon Ascent, can be knocked out quickly if not supported adequately.