Stringers will follow the rake of the stair.
The top and bottom can be raking or stepped, but the bottom can not be flat on the floor.
Even the base of a rail will follow the rake of the stair.
I would do this with a wall and add a raking opening to the top or SEO with a raking beam or roof.
Or morph as you seem to have done already.
One of the forum moderators.
Versions 6.5 to 25
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