ArchiCAD; how to make a sloping wall, you can find this very easy with the default settings
if you want to slope it over the longitudinal; you have to watch • ArchiCAD tutorial_SEO_cutting a wall above...
instead of the stair (but it is the same command "subtraction with upward extrusion"
(this tutorial is made by 'RPortierProductions', student civil engineer-architect of the university of Leuven)