This skill is critical in groups, particularly for tanks who need the aggro on themselves. In amongst berserkers and thanes of equal level, I have used Plague to get mobs to turn right around to attack me (in chainmail) instead of the puller with better range weapons.
This one style can make you look like a Midgardian Patriot missile.
Bari D'Hache
Assistant Weaponsmith
Midgard