Hey Stalkers! Can someone tell me - how to get Freak out! achievement? Should I got all mutation for 5 stalkers within main game or all mutation for 6 stalkers in {main game + seed of evil}? Cos wright now I have a second scenario and didn’t get this achievement 
In the DLC missions, the achivement Freak Out (Mutations) is not counting for me either.
3 of my characters have unlocked all the mutations during the DLC adventure (both left and right panels), but Steam is counting only the 2 characters that had all the left panel mutations unlocked during the main campaign.
nb: I know that achievement only counts the left panel. That is not the point. Just stating that I unlocked even the right panel, to exclude one hypothesis.
So for those trying to get all or more achievements, it seems the left panel mutations have to be unlocked during the main campaign. Which is surprising as many other main achievements now require the DLC (artefacts, notes, etc.).