The lich is one of Dungeons & Dragons' most iconic undead foes. D&D is far from the first piece of media containing undead spellcasters. However, the game is responsible for popularizing the term 'lich' to refer to a wizard so far gone in their hunt for power that they can transcend morality itself.
Source:https://www.cbr.com/dnd-creature-feature-friday-liches/