Sacrifice Mage

Summoned and then sacrificed, Ross Moreland's wish for excitement beyond his mundane PA job is granted in a way he never imagined. Transported to another world, his ritualistic death is interrupted when the banished sun god intervenes, returning him to life with a unique star-shaped mana core. This powerful core rapidly accumulates mana, posing a threat of fatal detonation if not discharged quickly. Ross discovers he can "sacrifice" this immense mana for extraordinary rewards, but his path leads him to join the very cult that attempted to kill him. Convincing the declining cult of his value, a cultist with a star core, proves surprisingly straightforward. However, mastering his mana core requires navigating a dangerous world filled with wicked nobles, zealous vampires, and a sunless city that shuns weakness. Ross must now learn to wield the power of Sacrifice to survive and thrive. The story offers an isekai experience akin to Ar'kendrithyst and Cultist of Cerebon, featuring magic exploration, training, slice-of-life moments, dungeon delving, and eventual cult development.