The comic activity began in 1985. Since then, Greg has created several characters (Sergio the Detective, I Vigili, I Mufloni, I Sottotitolati, Walter & Luca, Tubo) that he has published continuously in Lupo Alberto, Cattivik, Sturmtruppen, Mostri, Animal Comic, Star Comix, Stelle TV and Corriere della Sera. In addition, he illustrates the inner booklets of the Blues Willies and Milk & His Derivatives records and designs playbills for theatre shows, both for himself and for other companies. He has collaborated with the Capitoline satirical weekly Veleno.

In 2008 he published AgGregazioni, a collection of short stories, aphorisms, reflections and poems, whose caustic content constantly moves between the ironic and the bitter, without a hair on his tongue.

In 2014 he republished I Sottotitolati with new material on the occasion of Lucca Comics & Games.