Vileplume

At first glance, Vileplume seems to be absolutely inferior to Venusaur. She shares the same great typing yet loses out on a multitude of movepool options (namely, Power Whip, Leaf Storm, Earthquake, and Roar) and possesses poorer base stats (barring Defense, every base stat is less than or equal to Venusaur's). However, the little rafflesia still has a few advantages over Venusaur--most notably, Aromatherapy. Aromatherapy differentiates Vileplume from Venusaur and gives her the ability to function as a sturdy cleric with some special bulk. Like Venusaur, Vileplume also gets the valuable Sleep Powder, and somewhat reliable recovery in Moonlight.

Vileplume's main problem is that she is easily walled by Pokemon with a decent amount of special bulk. While such Pokemon do not stop Vileplume from accomplishing her main job as a cleric, they can simply set up against her while she struggles to damage them. In addition, Vileplume has an extremely shallow offensive movepool, as the only special moves she has are Grass- and Poison-type moves.