In 1818, he was initiated into the Filiki Eteria (Friendly Society) which was preparing the ground for the revolt.

He took part in several clashes against the Sultan's Navy in the eastern Aegean and soon realized that the Greek warships, being mostly converted and armed merchantmen, could not face the Ottoman ships of the line in conventional combat.

He therefore proposed the use of fireships instead, and sent Dimitrios Papanikolis to burn the Turkish frigate Moving Mountain anchored at Eresos on Lesbos.

Tombazis met fellow Hydriote Andreas Miaoulis in 1822 and reportedly realized the man's military genius, proposing him as admiral of the fleet.

After Tombazis withdrew from the admiralty, he continued to support the revolution with his ships and money.He died in 1829.