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.
At the start of the series, the Crescent Moon Alliance is a small guild with fewer than 30 members (only 19 were online at the time of the Apocalypse). The level of the guild's members is also low- only four players are level 90, and over half of the remaining members are below level 50. By the 5th novel, the guild's membership had grown to 65 members. Despite its small size, the guild is a member of the Round Table Alliance.
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)