Naganadel

Naganadel's Speed, Special Attack, and access to powerful STAB moves like Draco Meteor and Sludge Wave allow it to outspeed and OHKO many Dragon-, Grass-, and Fairy-type Pokemon such as Zygarde-C, Kommo-o, non-Choice Scarf or specially defensive Tapu Lele, Tapu Fini, and Jumpluff, as well as Normalium Z or Choice Specs Porygon-Z and non-Choice Scarf Garchomp. Furthermore, a strong coverage move in Fire Blast lets it hit Steel-type Pokemon that resist its STAB attacks for super effective damage. However, Naganadel has rather low defensive stats, making it very weak to opposing Pokemon that can outspeed or tank a hit and retaliate with either super effective attacks like Outrage and Earthquake from Mega Gyarados or powerful STAB moves like Giga Impact from Mega Lopunny, and Ice Beam from Greninja. Naganadel's shallow movepool leaves it with only Draco Meteor, Sludge Wave, and Fire Blast as clear options for moves without many choices for a fourth, making it a very linear Pokemon.