This type of virus (e.g. Tequila) infects multiple objects. Running an exe file infected with the Tequila virus puts itself in the master boot record ( MBR) . When the computer is booted the Tequila master runs from the boot record and goes to the memory resident. If Tequila memory resides , it infects exe files. Other viruses such as comic , exe and MBRs interchangeabley infected Anticad . How many again attack com, exe, MRBs and device drivers.