Interesting question. According to this site: http://doom.wikia.com/wiki/Sales http://doom.wikia.com/wiki/Sales between 1993-1999 Doom and Doom II sold a combin

Interesting question. According to this site: http://doom.wikia.com/wiki/Sales http://doom.wikia.com/wiki/Sales between 1993-1999 Doom and Doom II sold a combined 4 million units (gross over $120 million worldwide). Not sure what they made from licensing.