Hi. I've downloaded the game 2 days ago (so it might not be the freshest version?) and I found a weird bug:
After having attacked three doppelganger, they turned into harpies but kept forming a group by themselves (not mixing with the harpies nearby). This screenshot might help to understand the problem : https://gyazo.com/9b6852cfb01f5c3348bc09b7bd35d2cf
(Insane difficulty)
It was fixed the next turn : https://gyazo.com/cdce84514efbda7b34061ea4b14a3a04