The Crescent Moon Alliance is the secondary guild in the light novel and anime series Log Horizon. It is a small guild that was created before the Apocalypse and a member of the Round Table Alliance. Its guild master is Maryelle. The Crescent Moon Alliance is seen to be a guild for training low-level players (e.g. the summer training camp at Choushi Town) and a sister guild to Log Horizon due to frequency of interactions.
A medium-small guild operating in Akiba, the Crescent Moon Alliance does not have any specialisation per se and instead focuses on providing beginner to mid-level players with a friendly and comfortable gaming environment. It becomes heavily involved in the politics of Akiba after the Catastrophe and is later one of the founding members of the Round Table Council.
After the founding of the Round Table Council and the disbandment of Hamelin, most of the newbies decided to join the guild due to their part in their rescue, thus the guild gained a reputation for training newbies on the aspects on Elder Tales and how to survive in the new world.
The guild is the main focus of the spinoff Honey Moon Log, which reveals their lives outside of the game prior to the Apocalypse, and the viewpoint of the group during the chaotic first few days after its members got trapped in Elder Tale.
The guild occupies a seven-room "B Class" guild hall in the main guild building in Akiba, which Shiroe considers to be a perfect fit for them. It is divided into four general rooms, a workshop, a storehouse, and a meeting room. Maryelle describes the hall as "user-friendly."
- Maryelle (Guild Master/Lv.90 Cleric-Woodcrafter)
- Henrietta (Lv. 90 Bard-Accountant)
- Shoryu (Battle Team Leader/Lv. 90 Swashbuckler)
- Hien (Lv. 90 Assassin-Rogue)
- Serara (Lv. 58 Druid-Housekeeper)