Rather than fall in line with the prevailing, highly stylized "Green Helmet" look on trees like this here, I thought a closer crop of foliage at the top around the rims of the two fused, monolithic trunks might add an air of fantasy or adventure to the image, as if it shows a few trees surviving way up on these rock-like spires. It's early in development, and your milage may vary, but enjoy if you can!