Assassins Fraternity (Bencoolen) is listed as a muay thai boxing gym at 180B Bencoolen Street, #04-05, The Bencoolen, Kampong Glam, Singapore. It holds a 5.0 rating from 50 Google reviews.
A good muay thai gym is judged first on the coaching and on how carefully beginners are brought in. Before any pad work or sparring, a sensible coach teaches stance, footwork, shin conditioning and basic clinch safely, and matches partners by size and experience. Watch a class before you join, and notice whether the instructors explain each drill and correct form. Many regulars find that the first few months are about technique and fitness, not fighting, so it helps to set that expectation early. Ask about the contract terms, the gear you need to buy, and how classes are booked.
Bencoolen Street is a short walk from the Bugis MRT and the Kampong Glam shops, so the gym suits people who train after work in town. For anyone in the neighbourhood, Assassins Fraternity on Bencoolen Street is worth a visit to see whether its classes suit your level and goals.