For this image I took the original and processed it with Leonardo Canvas in the first step and replaced the heads. After that I corrected details (Reed had strange ears). After that I put a light structure over the heads with Photoshop.
Then back into Canvas and expanded the image left and right and also added some clouds. I manipulated the rocks a bit and other little things in the image.
I wanted to keep the character of the original heads, but also have the comic touch and still remain relatively realistic.