Dusknoir

Dusknoir is, in a nutshell, outclassed. Holding the dubious honor of being the only Pokemon in a lower tier than its pre-evolution, Dusknoir struggles to find much use in the RU metagame. This is because all of its positive points are offset by very negative points. Its incredible base 135 defenses are let down by a laughable base HP of 45, as well as a lack of reliable recovery outside of Pain Split, which is relatively easy to play around. Secondly, while Dusknoir's Attack is very usable, it does not have any powerful moves in its arsenal, with its most powerful STAB move being the weak Shadow Punch. This leaves Dusknoir outclassed offensively by Golurk and Rotom and defensively by Spiritomb and Misdreavus. However, courtesy of its Ghost typing, Dusknoir is capable of spinblocking Cryogonal and Kabutops, two common spinners in the tier, giving it a niche as a tool to keep entry hazards on the field. Dusknoir can also reliably take on Fighting-types such as Hitmonlee, Gallade, and Medicham one-on-one. Overall, before using Dusknoir, consider the existence of the aforementioned better Ghost-types, lest it prove to be a waste of a teamslot.