28 parts Complete A Tensei Shitara Slime Datta Ken / That Time I Got Reincarnated As A Slime fanfiction.
Rimuru Tempest, once known as Satoru Mikami, is faced with a dilemma much different than anything he's ever had when building the Jura Tempest Federation. Although it is incredibly convenient to have a reincarnated companion from Earth, Rimuru soon finds the cultural divide between him and his fellow reincarnate to be a barrier that threatens to end their acquaintanceship.
Hunter Revin was once a hard-working gunsmith. Killed during the American Troubles, his dying regret over having accomplished very little in his first life resulted in his reincarnation. With knowledge on how to create some of the deadliest and most efficient handheld weapons of the 20th to 21st century in his head, how will this gun-loving American contribute to changing the face of a pre-industrialized magic-dependent world?
This fan-story is based on the anime/manga adaptation.