The capability of instant pulse and restartability is a fundamental specialty of in-space propulsion. A hypergolic propellant is considered the most suitable propellant combination for in-space propulsion. Traditional toxic hypergols have been extensively adopted in satellite/interceptors due to their high performance and good storability. Recently, Green/low-toxicity propellant has been remarked as the replacement because it can offer benign safety procedures, handling infrastructure, and significantly reduce economic expenses. Herein, the challenges ahead of the feasibility of substituting such toxic hypergols in the practical application were demonstrated; the study was aimed to resolve typical poor ignition performance and enhance understanding of reactive burning spray. The hybrid use of catalytic and redox reactions reduces the ignition delay to less than 3 ms, which is comparable to that of hydrazine/nitrogen tetroxide. Furthermore, the visualization of burning spray was implemented using a blue light spectrum. The dynamic pressure ratio significantly varied the hypergolic burning spray structure. The inherent hypergolic instabilities were injection mixing explosion and popping throughout the comprehensive analysis based on the visualization in sync with pressure perturbation. Moreover, the hypergolic combustion under pressure exhibited shock instability, and the suppression strategies regarding modification of thruster dimensions and propellant were attempted.