CALL TO ADVENTURE! Defeating Dungeons with a Skill Board (Manga) Vol. 9

Haruki and Karen participate in the stampede cleanup at Kamuy Kotan. A staircase rising from the heart of the dungeon leads to Kamuy Rock, where a knight in jet-black armour awaits. The knight's strength is beyond anything they've ever faced. Can Haruki and Karen win this battle against a legend?!