The most distinguishing weakness of a lycan is silver, and all lycanthropes are psychologically bound to the phases of the moon. Ironically, many of a lycan 's other weaknesses are derived from its unique physical attributes.
Silver - Lycan have a severe allergy to silver. Superficial skin contact will result in redness and irritation, and a burning sensation that intensifies with increased pressure or prolonged exposure. Silver-inflicted wounds require healing times matching those of a normal human's, and often leave a scar. Silver wounds cause painful, physical burning in addition to pain associated with the particular type of wound. If the silver remains lodged inside the body, cellular proteins will begin to breakdown, causing progressive, localized damage similar to a chemical burn.
Full Moon - Though not understood why, lycan have a psychological link to the phases of the moon.
- Periods during the half-moon phase are when lycan will maintain the greatest self-control, and most balanced, human-like behavior.
- During a new moon, individuals may carry on with more indifference, demonstrate more sedate behavior, or behave more carefree than normal.
- During a full moon, individuals usually exhibit signs of impatience, anxiety, restlessness, and/or aggression. Younger and recently-turned lycan typically cannot maintain the mental and physical control necessary to prevent outbursts of extreme behavior and chaotic thought patterns. This quickly leads to a feral state, in which the conscious mind goes haywire, shutting down (much like a seizure) and an uncontrolled transformation to either feral or wolf form occurs. At this point, mental control is replaced by a primal subconscious, driven solely on primitive instincts (fight-or-flight) and basic needs (food, etc).
High-Frequency Noise - The effect of high-pitched noises can range from irritating, to deafening, to dangerously incapacitating - depending upon their intensity. High frequency noises at extreme amplitudes can rupture ear drums and cause severe damage - leading to temporary loss of hearing and vertigo.
High Metabolism - Though not a direct weakness, lycan require large intakes of food to function at peak levels. Protein is the primary necessity, required for the near-constant cellular regeneration that takes place during transformations and healing. Though lycan can survive without food longer than humans, the diminishing effects on muscle mass and energy can be just as drastic.
Scent - Lycan maintain their unique scent even when in human form. Though meaningless to other humans, this does make it more difficult for lycan to blend in as 'human' when among others with keen olfactory senses.
Wolfsbane - There was once a story that surrounded the legend of wolfsbane and Lycans, though the true story itself has been long lost to the ages. The general assumption is, however, that after the Mother had cast out the Crone and her children into the night, and the maiden and her kith too had been punished, that the world was revived. Across the fields and forests that had been the battleground for the Great War, which would eventually become known as the Great Divide, a new flower grew. One in the place of each fallen Damphyr. A flower perfectly representing the beauty and cunning of the Crone Goddess. Poisonous to all that touched it. Especially so to the Lycan. This flower would come to be called Wolfsbane.
The flower itself has many uses against lycan. It emits a smell that is devastating to their senses, and if ingested it could easily prove fatal. NOTE: This weakness is not commonly known. Please have a very good reason (not searching books or the internet) to know this.