Liches

Liches are arguably the most powerful echelon of undead. They are mortals who have used unholy, often necromantic spells and rituals to prolong their lives beyond their natural spans. They retain their sentience, but their bodies continue to decay. Whether undead status is intended or an unexpected side effect of perceived life-prolonging processes, the aims in each case are the power and wisdom that come with countless years of unlife.