Backstabbed in a Backwater Dungeon Vol. 2 (manga)

A MOUTHFUL OF VENGEANCE!The young adventurer Light was betrayed by his party and abandoned in the deepest levels of a dungeon called The Abyss with nothing but his magical gift of Unlimited Gacha-a power that had previously created unlimited garbage. But supercharged by The Abyss itself, the gacha unlocks its full potential and Light unlocks new allies: an astounding army with which to exact his revenge and conquer the world!Having dispatched the beastman Garou, Light sets out to find Sasha the Elf. In the meantime, he and two companions head to the bordertown of Dagas to gather both information and glory.

The Dagas dungeon offers ample opportunity to raise their adventuring ranks...so long as nobody cuts the line!