I didn’t think I’d said it loud enough for anyone to hear, but Telestrian picks up on it. "Yes, antigenic shift is one consequence, but more drastic changes are also possible. The reason magically activated viruses aren’t used is that nobody knows what they’re going to turn into." Her voice is cold—or maybe it’s just my reaction to what she’s saying. "The antitumor virus, tailored to attack cancerous cells exclusively, shifts and starts attacking only those cells that aren’t cancerous.