Is It Wrong to Try to Pick Up Girls in a Dungeon?, Vol. 6 (light novel) — Fujino Omori

"Hestia, I challenge you to a War Game!"
"What's with you, Apollo?"

A War Game--an all-out proxy war between gods, and the winner takes all. But what is it that Apollo wants? Hestia's beloved Bell Cranell, of course! With a week to go until the Game, things are bleak enough, but then Lilly is kidnapped by the Soma Familia. The outlook isn't good, but Bell has made many friends through his adventures, and they won't stand idly by. The familia myth continues!