There’s nothing like a mod that brings back the classics, which is precisely what Rainbow Six: Black Ops has done.
Rainbow Six: Black Ops is a total conversion for Rainbow Six: Rogue Spear that recreates every mission from the first seven Rainbow Six games, including special missions that were only ever released in South Korea. Rogue Spear is the second game in the franchise, so you’ll be playing through the missions with the classic tactical planning phase and that iconic ’90s polygonal look.
In total, the conversion gives you access to 56 story missions, the original intro video, updated textures and corrections, the restored sound files and custom registry keys so Windows 7/8/10 users don’t run into any issues.
It’s an incredible piece of work and it’s available on ModDB here. You’ll need Rogue Spear for this to work, obviously, but GOG only has the original game available. The Rogue Spear disc, however, is available on the Internet Archive.
Correction: Rogue Spear is the second game in the franchise and not the original, so the copy’s been clarified to fix the error. Apologies.