Haunter

Haunter is one of the tier's most potent offensive Pokemon due to its solid coverage, great power, and nearly unrivaled Speed tier, letting it pose a threat to revenge killers like Murkrow and Pidgeot as well as walls like Sableye, Wailord, and Roselia. Additionally, Haunter is quite self-sufficient; it can utilize utility moves such as Thief and Toxic to make breaking through foes such as Chimecho and Flareon easier. Haunter can even function as a late-game sweeper, utilizing Endure and a Berry to boost its Speed or Special Attack to become an even greater threat to weakened teams. Furthermore, Haunter is one of two viable Ghost-types in the tier and possesses a great amount of defensive utility; it can spinblock against Hitmonchan, check Normal-types like Pidgeot, and switch into Ground-type attacks from Pokemon like Choice Band Relicanth. Haunter's only real shortcoming is its pitiful bulk, although even then it can take advantage of Choice-locked foes like Hitmonchan and Raticate to switch in and set Substitute.