I am currently testing a pattern by @Kreaida. Their work inspired me to create something myself. It turns out this sort of thing already exists (of course). Tapestry!
My question to you experienced tapestry people:
How many strands of yarn is the max?
The pattern I’m thinking of requires 6 colors.
I honestly don’t think there would be a limit.
It’s limited by the size of your design, the detail of your design, and the weight of the fabric you are working on… And if course, the type of floss you are working with.
You can do tapestry on very large canvas meant for rugs, or medium for upholstery, or light for a pillow, or plastic that can be cut and sewn together for 3 dimensional objects (oh my, I would love a Renaissance of plastic canvas! Back to the point, it’s as varied as knitting and crochet