Beedrill

Mega Beedrill is one of the fastest Pokemon available, with the strongest U-turn in the tier. This enables it to easily wear down opposing switch-ins such as Melmetal and Rhydon while pivoting to other counterplay to set up a late-game win for itself or a teammate. Mega Beedrill checks and forces out many prevalent threats such as Mew, Starmie, and Alolan Dugtrio. The primary downsides of using Mega Beedrill are its vulnerability to Stealth Rock and its frailty. Keeping Stealth Rock off the field for as long as possible greatly helps its longevity and can prevent it from being picked off by weaker priority from Pokemon such as Dugtrio that it would check at full health. Mega Beedrill will likely rack up Stealth Rock damage due to being forced to switch out against threats that it cannot OHKO and will OHKO it back, which makes the prevention of Stealth Rock all the more important for Mega Beedrill's continued usefulness.