Sneasel

Sneasel is tied with Persian as the second fastest Pokemon in the entire metagame, which, alongside its decent base 95 Attack and unique dual typing, would allow it to perform wonderfully as a Swords Dance sweeper or Choice Band wallbreaker. Unfortunately, both of its STAB types are special, and it only has base 35 Special Attack, meaning Sneasel must use non-STAB moves if it wants to make use of its much higher Attack stat. Sneasel is also exceedingly frail and has five glaring weaknesses, necessitating an immense amount of team support in order for it to function. Even so, Sneasel has perfect neutral coverage in Shadow Ball + Brick Break, and in a metagame dominated by Psychic-types such as Hypno, Solrock, Lunatone, and Grumpig, as well as Fighting-weak Pokemon such as Kangaskhan, Cradily, and Walrein, perhaps it's not all bad for everyone's favorite icy weasel.