Firstly, unlike what is generally expected from Emperor cards, the Noblet faces to the right. In many ways, this is perhaps more apt, as profiles to the right would show the 'right' side of the face (though there are instances of the Holy Roman Emperor with semi-profile orientations to the left), the left-hand orientation of the card in TdMs in general has always fascinated me. Therefore, when I first looked at the Noblet, I was not surprised that here his orientation is more as to 'be expected'.
Yet here is the quite strange and at-odds detail - a detail I partially saw earlier, yet at first took to me more a 'shadow' effect.
Let's briefly look at the card as a whole first, and then at Robert's accentuation of the detail with Photoshop assistance:
Here it can be seen that there appears lines that nearly mirror the image towards the right of the card (no other card in the set do this, by the way). Accentuated, here are the details:
I'm not sure how to explain nor account for this. Presumably, the woodcut is made from a large block and a whole sheet printed. It's as if such occured, and then the image was 'washed' and a new imprint was made - an imprint that would have required a different and reversed woodblock to have been used.
Again, not sure even why this would have been the case - the only thing I can think of (in terms not of symbolic significance, but of practical workshop one) is that stencils had been prepared for the inverse image, and washing the Emperor and re-imprinting it afresh from a single woodblock may have saved having to redo a whole set of stencils.
In any case, a quite strange detail... and one worth further consideration!