MS-DOS viruses that lived on computers in the 90 decade are reborn at the Archive.org Online Museum.
The Malware Collection will introduce you to browser you, viruses that hit MS-DOS in the 1990s.
Many of them were incredibly destructive, but the mentality was different. They showed stunning messages or played music as they slowly destroyed your computer.
If you are thinking of visiting the Museum, don't be afraid, its destructive parts maliciousυ software have been removed, and it's quite interesting to see how the viruses of the past were created and what they did to computers, other than destruction.
Let's mention that back then there was no software protections from viruses and so if you got hit by a virus you would have to install MS-DOS from scratch.
https://archive.org/details/malwaremuseum