I hear that you can grab the impregnation talent in the alchemy tree and then you can start using your mutagen slots because in chapter 3 you'll. The Witcher 2: Assassins of Kings Enhanced Edition would be to get as many Mutagen slots as I could, slot them ALL with Greater Strength. I did start my game with my old Witcher 1 saves. 2. avatar. Unrated_Edition: Mutagen slots aren't appearing for me on any of the Training.