I used brush pen and watercolors. The most challenging part was holding back on excessive pen lines to render the fur, using patches of paint instead. Although I think the background is a bit dark and there a few mistakes, I feel that learned from this.
Doodle cards printed with foil and metallic ink - year 1999! I used a desktop printer that could reproduce metallics / foils / spot UV. They don't make desktop printers like that anymore.