Vileplume

Vileplume, on her own merits, is a very respectable Pokemon, but she has always received the short end of the stick from Game Freak. In the same generation she was introduced in, Game Freak saw fit to introduce Venusaur, who has better stats than Vileplume in everything other than Defense. Unsurprisingly, Vileplume has been relegated to at least a tier lower than Venusaur throughout the generations, and this honestly hasn't changed much in BW. Furthermore, despite the banishment of Venusaur and Roserade into higher tiers, Vileplume receives significant competition in RU from the newly introduced Amoonguss and now Eviolite-wielding Roselia; nonetheless, she is able to distinguish herself from them with her unique traits. Defensively, Vileplume has significantly more physical bulk than Roselia and boasts Aromatherapy over Amoonguss, so she acts as a neat mix of the two. Unlike the two, Vileplume is also capable of acting as a strong special attacker by utilizing her great STAB coverage and as an excellent tank due to her mix of power and bulk. Make no mistake, Vileplume is not a Pokemon to be underestimated.