Ari No Su Dungeon E Youkoso!

Ari No Su Dungeon E Youkoso! summary:

When I woke up, all I had were an unfamiliar room, a crystal, and no memories—just “me.” Awakened as a Dungeon Master, Dan starts with a few points and uses them to summon ant monsters to expand his dungeon. Alongside the ever-increasing and evolving ants, he repels intruding enemies, occasionally recruits allies, builds an impregnable mega-dungeon, and aims to find new happiness and everyday life within the dungeon!