Flashbacks is a five-movement piece for percussion trio. This work aims to explore the unique sounds and effects of various combinations of percussion instruments. Each movement emphasizes a distinct theme: motif and development, timbre, or atmosphere. To achieve the appropriate sounds for each theme, several unusual percussion instruments, such as the barimbulum and exhaust pipes (metal pipes), are selected for this work. The barimbulum is a crude instrument designed by Evelyn Glennie, the acclaimed Scottish percussionist. This instrument comprises several long metal bars attached to a large wooden box through side holes. It produces a rough, loud, and metallic sound due to the fast, massive, and frequent vibrations caused by strikes. With a total of 19 percussion instruments and several combinations of them, this work features the compound timbre of the percussion instruments, highlighting each movement’s unique theme.