Just as planned, the three who fused into one monster have finally been defeated. With the help of Atlas and of course, Gin. We managed to decapitate both remaining heads It's not hard, to be honest, and since their pattern of attack is pretty much just that slamming attack and manipulation of the fleshy membranes, it was very easy for us to dodge it and how low their defense values are.
Of course, the plan wasn't flawless. Since Gin was hesitating during the beginning, his cut wasn't deep enough that I have to use force to support Gin's attack and firmly bury the katana's blade into the neck of the fleshy monster and effectively cut off its neck.
The moment the fused body died and lost all of its HP, the walls and floor that are made of flesh and meat have disintegrated into pieces. Nothing was left behind and the floors and walls have returned to how it was how I remembered the place in the past timeline.