"Heart of Fire" is a comic story spanning three pages. The writing was done by John Ostrander, the pencil and ink work by Jan Duursema, and the colors by Dan Jackson. It was published as a serial in Dark Horse Extra issues #35, #36, and #37.
Following the events depicted in Star Wars: Republic: The Hunt for Aurra Sing, Jedi Master Quinlan Vos is recuperating within the Jedi Temple located on Coruscant. While he is present in the Meditation Garden, Master Vos is disturbed by a young female Twi'lek Padawan. Quinlan identifies the girl as Xiaan Amersu, whose Master met their end at the hands of Aurra Sing. Xiaan inquires about Aayla Secura and presents Quinlan with a shimmering stone referred to as the 'Heart of Fire'. He had previously owned this stone, gifting it to Aayla, who then passed it on to Xiaan. Now, Xiaan is returning it to Quinlan, urging him to perceive the visions held within the stone, which he then proceeds to do.
Heart of Fire finds itself reprinted within Star Wars Omnibus: Menace Revealed, although it is designated to occur around 31 BBY. Consequently, it is positioned before The Hunt for Aurra Sing story arc within the Omnibus (which is itself dated around 30 BBY), despite the events of Heart of Fire taking place after the initial issue of that arc.