Defenders of Space (1987)

"Nicholas, a ruler of the Zinba Empire, wants to expand his territory and Earth is his main target. After Nicholas destroys City Orion and Earth's defences, three youngsters must find the Phoenix King, the only hope for Earth's survival against this all-conquering foe." Official Synopsis. Hong Kong English Dub of the 1984 South Korean cartoon "Immortal Robot Phoenix King" (불사조 로보트 피닉스 킹)