Mar Amongo learned the comics profession from Nestor Redondo, an artist that was of influence in Amongo's further career. He began his career working for Extra Komiks with Ramon Marcelino. He subsequently went to work for other publications, such as Romansa Komiks, Modern Komiks, Tagalog Klasiks and Espesyal Komiks. He illustrated a comics adaptation of Jose Rizal's 'El Filibusterismo' for Manlapaz Publishing.
Like many Filipino artists, he eventually went to work for the US market. He worked for such DC titles as All Out War, G.I. Combat, Ghosts, House of Mystery, Secrets of Sinister House and Weird War Tales. Amongo worked as an artist in the Middle East from 1983 to 1994. Back in the Philippines, he took on religious graphic novels like 'Talons of Time' and 'The Tiger's Fang' for Enckankar. Mar Amongo died in August 2005, at the age of 68.