Wolfsbane

Physical Description. These plants possess dark green, deeply lobed leaves with serrated edges; the tall stalks of wolfsbane plants grow quite tall (up to 4 feet) and bear a number of elongated keel flowers that vary in color in shades of pink, purple, or dusky blue. Below, the roots of this plant form a large, bulb-like structure with several smaller adventitious roots that help to anchor them in the rocky soil. Wolfsbane originated in the now-lost Material Plane Barovia came from and is similar to common aconite found across much of the multiverse.
Wolfsbane prefers rocky, well-drained soil and what meager light they can get. Interestingly, cultivars grown in domestic gardens lose both the virulence of their poison, as well as their color. When grown for ornamental use, the plant is shorter; the blooms are less showy, and the poison is weaker, causing milder forms of sickness when compared to their wild brethren.
Notable effects / uses. Every part of the Wolfsbane plant is exceptionally toxic when ingested, causing stomach upset, extreme nausea, sweating, and heart palpitations. Even small doses of Extract of Wolfsbane have proven fatal, making it a perennial favorite of the would-be poisoner. Alchemists have distilled this poison to strengthen it even further and created tinctures that have proven especially effective in eliminating lycanthropes of all stripes.
Of note: folk medicine from Barovia states that fresh wolfsbane can cure lycanthropy if ingested within hours of getting bitten. Whether these reports are true, however, is difficult to ascertain as few are willing (or able) to tell the tale or risk dying from the poison.
Biome. Mountainsides, often cultivated in towns (Barovia)
Rarity. Common

Scientific Name
Aconitum variegatum