I don't remember the artifact's description, but I always thought that Marckel's skull wasn't specifically his skull, but rather someone else's skull that he always carried around.

In Vitaly Zykov's series of books dedicated to the adventures of Kirsan Kaifat (a Russian programmer who ends up in another world), there is a plotline in which the great necromancer Marckel gives his body to a necromantic apprentice (I don't remember the name) to complete a task, during which the apprentice dies (killed by the great dark elf Vorek Minosh). As a result, Marckel, returning to his body, sees that it has been killed, and the last thing he manages to do is turn himself into a Lich and command him to start a war with the whole world. The armies of the undead, raised by him, destroy the pirate-barbarians of the Serpent Archipelago, and then attack the island of mages, Nold, where the Lich is finally stopped and beheaded, and this is how this artifact appears.

In general, I personally really enjoyed this series of books, I recommend it (sometimes it seems that he writes under the influence of the Heroes game, although much of modern world politics can also be seen in it).

http://zayci-tyt.ru/books/122984-polnaya-seriya-vitaliya-zykova-doroga-domoy-7-knig-2004-2015-fb2.html

sorry for the slight off-topic ;)