Prototype and Promo Cards

There were 3 promo cards and 1 prototype card distributed before the release of the 1993 Marvel Masterpieces. The prototype card features She-Hulk with the work "Prototype" across the back. The 3 promo cards featured Dare Devil, Hulk 2099, and Venom. The backs of the promo cards contained release and set information. As far as my knowledge goes, the She-Hulk card was distributed to card dealers as a prototype card. The Venom promo card was distributed at the San Diego Comic Con. The Hulk 2099 promo card was distributed within the Tuff Stuff's Collect Oct-Nov 1993 issue (see pic below). The Dare Devil Promo was supposedly distributed within a Hero Magazine but I have yet to verify this information.