In early 2000, having completed a Master's degree in Cell Biology and Physiology, Sébastien Rossi decided to do a 180 and become a 3D graphic designer. Thanks to his studies, he had acquired some technical skills, and soon turned to 3D FX and scripting. In 2009, he became FX supervisor and worked on feature films and animation series for some of the leading French animation companies (Illumination Mc Guff, Mikros Animation, Duran Duboi, etc.). He took on the role of CG supervisor for the Arcane series at Fortiche Production in 2017, a position he held throughout season 1.