Describe the feature

Twisted corner block like this:

for clean slopes on already sloped plates
example of shape being used in Avorion: (green is the shape and red is the mirrored version)

vertex pattern: (O is empty X is vertex, left is base shape right is mirrored version)

top
XX | XX
OO | OO
bottom
XO | OX
XO | OX

Looks useful, I'll add it to the list of planned blocks