The article highlights the research on the newly identified virus that its size challenged the definition of a virus. It features the previously identified virus Acanthamoeba polyphaga mimivirus, described as a new strain of the giant mimivirus that has its own viral infection, and followed by a much larger virus, named as mamavirus because it resembled the main features of mimivirus. It also discusses the finding of another virus in the Acanthamoeba polyphaga cells which was named Sputnik.