What favored medium among artists who painted in the international Gothic style?

Artists of the International Gothic style favored tempera on wood panels as their primary medium. This technique allowed for vibrant colors and intricate details, which were essential to the ornate and decorative nature of the style. Additionally, illuminated manuscripts were also popular among these artists, showcasing their skill in fine line work and rich coloration. Overall, these mediums facilitated the intricate and elegant aesthetic characteristic of the International Gothic movement.