Inner Prism is great - inner sloped prism is also excellent, but it seems like a way to connect an inner prism with slopes (as seen in the image) is impossible right now, unless I've somehow missed the block I needed.
ChefTheChefChef commented
For further clarification - something like the regular slope block, just with the green-marked area removed, to fit the inner prism.
XFactHD commented
Sounds like a reasonable addition, I'll add it to the list of planned blocks