In 1993, a booklet by H. van Haeringen was published by Coulomb Press Leyden, Leiden, the Netherlands. The
book, called Superschaak en
Monarch was a Dutch book, giving the rules of two chess variants. It has 32 pages, ISBN 90-71421-25-2.
Later, a translation of the book in English appeared, and a larger book, in Dutch.
In the book, the rules of Superschaak (Superchess) are given. Players have freedom for several details of
the game. A large collection of
50 different pieces is described, and the players should agree which of these are used. There is also a
choice of board: 10 by 10, 10 by
8, 8 by 10, or 8 by 8. But there are also fixed rules, e.g., where pawn-like pieces should be at the start
of the game.
The rules are clearly described. Most striking is the cover of the book, with really beautiful wooden
fantasy chess pieces.
Monarch is a variant of the game, with differences at some details.
Link
More information can be found on the websites of Superchess: