If you own an old Heretic CD-ROM, simply copy the heretic.wad from the CD to your hard drive. It will work with modern source ports without the CD check.
, the most reliable and legal method is to purchase it through a digital storefront. This gives you the official HERETIC.WAD file, which is necessary to play the complete five-episode experience. 🛒 Where to Buy and Download download heretic wad full
It is cheap, 100% legal, supports the developers, and guarantees a virus-free file. If you own an old Heretic CD-ROM, simply copy the heretic