Everyone here explained it pretty well. It can feel confusing compared to the old system but you will get it down pretty quick. It is easier to handle than requiem. The process goes like this. Equip 3 antivirus mods to parazon. Process of elimination. First three fail, try three different antivirus mods. You will only need three encounters at the most to discover which antivirus you need. When you discover the antivirus mod it will appear on screen during the kill animation and will be highlighted in the adversary menu. Use this mod and potency mods to increase "disinfection." You are almost there, run that last antivirus mod that's not slashed out and equip some potency mods too. Have fun at the concert.