4D-Chess (4x4 array of 4x4 boards) had been investigated by Maack (famous for his 3D-Chess) in the early 20th c. Dawson wrote a paper about it in 1926.
Also V.R.Parton was much interested in this. Let's mention his Sphinkian Chess (3x3 array of 4x4 boards). And above this, his Ecila Chess in 1970 with a cubic 2x2x2 array of 2x2x2 cubes, a 6D-Chess.
4D-Chess (4x4 array of 4x4 boards) had been investigated by Maack (famous for his 3D-Chess) in the early 20th c. Dawson wrote a paper about it in 1926.
Also V.R.Parton was much interested in this. Let's mention his Sphinkian Chess (3x3 array of 4x4 boards). And above this, his Ecila Chess in 1970 with a cubic 2x2x2 array of 2x2x2 cubes, a 6D-Chess.