A start-up activity, Refining Master of Injections Matrix with Subject Matters Experts (SME)s, was held on 30th March 2021. 19 SME gathered in Le Meridien Hotel, Putrajaya, to determine the best approach to run the Anthrax Disaster Simulation Exercise, including scenario, gamification tool, tabletop exercise, participants, and platform. Relevant first responder, Emergency Response Team (ERT), biomedicine, veterinary medicine, human medicine, armed force (Police department), policy- makers, and government officials attended the activity to give their input on the preliminary scenario concept for the Master of Injection Matrix (MIM) development. Besides that, the activity provided initial collaboration in a friendly environment for further inter-agency engagement during the simulation exercise. However, after considering all factors, the simulation exercised was postponed due to the government’s Movement Restriction Order (MCO).