Kings and their courts

[bonanova]

Arrange the Jacks, Queens, Kings and Aces of the four suits { Spades, Hearts, Diamonds, Clubs }
in a 4x4 array, in such a manner that:

• Each row has exactly one card of each rank and one card of each suit.
• Each column has exactly one card of each rank and one card of each suit.
• Both major diagonals have exactly one card of each rank and one card of each suit.

Euler, the great mathematician, proposed the task of constructing a similar 6x6 array, but instead it was proven to be impossible.

Does a 5x5 array exist?

[CaptainEd]

Does this do it?

With G as the suit designation for “hippoGriffs”...

Using shdcG as the suits and akqjt as the denominations, here is a pattern that I think meets the specs

ah    tc    js    qG    kd

jG    qd    kh    ac    ts

kc    as    tG    jd    qh

td    jh    qc    ks    aG

qs    kG    ad    th    jc

[CaptainEd]

Presumably a green suit, but not the Eagles, that were tried in the 1930’s. I remember, but can’t find, a short story about someone bidding bridge against a demon, who wins the bid in no trump and starts leading weird green cards with monstrous figures on them. When the narrator couldn’t follow suit, the demon says “What? No hippogriffs?”