Drifblim

Drifblim is the epitome of uniqueness: it has a one of a kind typing with atypical stats, abilities, and movepool. These traits might imply greatness, but competitive viability does not work that way. Despite boasting three immunities, including to the common Normal-type, and a gargantuan HP stat—the seventh highest in the game—, the same typing that blesses it with the aforementioned immunities also gives it a glaring weakness to Stealth Rock, Pursuit, and the BoltBeam combination, all of which are common in NU. Add in puny defenses that don't match its HP and you'll realize that Drifblim is being held back. However, despite all of these negative features, Drifblim has a great ability in Unburden, which, combined with its extensive movepool, Drifblim is able to exploit it with great success. You might not deem this purple balloon threatening, but it will easily prove otherwise.