Schuld 
Min-Maxing My TRPG Build in Another World: Volume 9 Canto I [EPUB ebook] 

Erich and his party (not that Siegfried would admit to being a part of it) have made it back to Marsheim from the ichor maze, battered and bruised but all in one piece. However, the plucky munchkin’s luck is as bad as ever—a looming shadow threatens to end his adventuring career. With a little “nudge” from his oldest friend, Erich takes up a new scheme to rescue not just his own future, but those of all the friends and allies he’s drawn into his wake. Erich’s a scrappy young rookie no longer: it’s time for everyone’s favorite min-maxer to put aside build optimization and foster the kind of power you can’t find on a character sheet!