The Axii sign should allow Geralt to get one enemy to fight on his side for a short while. This sound extremely useful for fighting groups, but I was unable to get it to work so far.
What happens when I use it on an enemy is that he gets distracted for a second and some visual effect is visible on the enemy. But he doesn't attack other enemies and the whole thing lasts only a second or so.
Am I doing something wrong, or does the Axii sign just not work on many enemies?