The only way I know of to play HoMM3 w/o the CD is by downloading WoG. You can play either WoG or HoMM3. But you will not be able to play the SoD campaigns as they now are replaced by the WoG Campaigns. However, you can download the SoD Campaigns and put them in your map folder (Located in 3DO/Heroes 3/Maps section.) and then play them.
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