Reverese is encrypted with a variable key. The body of the virus
contains two filenames written backwards:
COMMAND.COM is infected by overwriting a block of zeroes inside it.
NCMAIN.EXE is not infected at all.
Reverse contains the following text, which is not displayed:
Reverse-948 Created by Renata G. from Lubin City in Sept 1993
Similar and also 948 bytes, but contains this text:
Red Spider Virus created by Garfield from Zielona Gora in Feb 1993
[Analysis: Mikko Hypponen, F-Secure]