Aksy sign, how does it work? (The Witcher 3: Wild Hunt)

I can’t understand, I pumped in the fire, the 2nd access line opened, there I studied the Aksy cat sign. is responsible for luring the 1st enemy to his side, put this skill into the slot and even strengthened it with a mutagen by 10%. Unless that this particular skill would work, you need to study the Axius skill that is located above?