[CSMastermind]

> The player’s choice is not restricted to pieces that have been captured previously

I grew up playing chess but my grandfather always insisted that pawns could only be promoted to captured pieces so when I played him we had to play a that variant.

I suspect this came from players not having extra pieces with their chess sets.

[vitally3643]

That and just avoiding the obvious advantage of promoting every piece to a queen every time. Puts more constraint on the game which usually makes for more interesting play