Holy Wisdom
Have traced the reference to its source.
My secondary source - an article of modern card-games - had no footnote.
I find a reference in Seznec, which perhaps the former source has misquoted (or perhaps they had some other.) It occurs where Seznec is talking about the so-called Mantegna tarocchi.
pp. 139-40 of Seznec's Survival of the Pagan Gods:
gives a paraphrase of Brockhaus, who is said to related that this ['Mantegna']Tarocchi was devised and made in Mantua during a long council held there between June 1454 to Jan 1460 (when) - says Seznec, "they allegedly served as a pastime for three members of the Council, the Cardinals Bessarion, and Nicholas of Cusa, and Pope Pius II"
After summarising and classifying the images of the pack, it is actually Seznec who then says, "... we do not know [this ecclesiastical] game's rules in detail, but there is no doubt it was played seriously, with a feeling that each piece was, as it were, a piece of the divine chessboard (D: or - "map"). And we may apply to it the words used by Nicholas of Cusa (himself) to describe a similar game ... which he uses as an illustration for his philosophical thought: "this game is played, not in a childish way, but as Holy Wisdom Played it for God at the beginning of the world."
There's actually no reason why Nicholas might not have created our numerical games; he had the necessary expertise, experience of critical places and people etc. as any biography will show. The written account of his own construction 'de ludo globi libri duo' is not certainly dated, but is generally supposed to have been written in 1460 or so. Once again, the ludus is set in the atmosphere of the 'tutorial' with imagery used to fix, and explain, the content of a teaching-'text'.
But here - now mathematics and philosophy is the focal subject; and the imagery (verbal or otherwise) rings variations on ball-throwing.
I don't know why the question of Nicholas' possible invention of the number games has not been considered; given his curriculum vita, he'd seem a prime candidate, even as early as Ferrara.
For details of Cusa's book see...
(is this Michael below 'our' Michael, by the way?)
http://www.wlym.com/~animations/ceres/PDF/Michael/history1.pdf
For Nicholas' connections to THe Byzantine court and other regions and peoples equally relevant see:
http://www.newadvent.org/cathen/11060b.htm
And here again is the 12thC Greek angel - already on the pre-1377 thread - but handy here: