CALL TO ADVENTURE! Defeating Dungeons with a Skill Board (Manga) Vol. 11

WHAT LURKS BENEATH Operation retake Okushiri Island continues! Various teams compete to clear out as many monsters as possible. Overseeing it all is Masatsugi, the strongest adventurer.
Haruki’s team has been impressing their live-stream viewers until disaster strikes. A massive hole opens beneath their feet, landing them in an underground dungeon and separating Haruki and Karen from Akane. As the two look for an exit, they stumble upon an underground lake and the boss that dwells within it. Can Haruki come up with a strategy to beat a foe that commands the waves?!
Series Overview: Since the discovery of fantastical dungeons all across Earth, slaying monsters and clearing out dungeons has become a popular pastime. Twenty-seven- year-old Karaboshi Haruki dreams of gaining recognition as an adventurer, but he’s got two monstrous problems: he’s socially invisible and has literally no skills at adventuring. When a dungeon suddenly appears in his garage, however, he finds a skill board that allows him to level up faster. The dungeon-diving adventures Haruki has always dreamed of are just getting started!