I have run into the issue that I want to reshape vanilla walls for a diagonal angle, and the existing wall-pieces just aren't capable of doing so. Is there a particular tool I can use to just "bend" the corner pieces to fit the angle, or maybe just using vertex welding or something? My Blender skills are unfortunately rather more rudimentary than my GIMP skills.

The offending part, which needs to get bent, is right at the bottom where the wall segments aren't fitting the way I want them to. Don't mind the top, given the wonky topography of Gorizia Castle I'll probably to add a new tower segment up there regardless. Though speaking of which- I've heard that to get artillery "on walls" you need to basically cheat by getting terrain and cladding it with a wall model? I am sort of thinking of doing that in that round "tower" bit down in the middle right if so.

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