Pawn Chess

This game allegedly was invented by "dzebra" (real name unknown) on the Fantasy Strike forums.

Rules

This is a modest chess variant where a pawn promotes into the first non-pawn piece your opponent has captured and hasn't been placed back on the board yet, rather than selecting the promotion yourself. So effectively you would be making a queue of pieces to promote into.

It isn't specified what happens if you promote when none of your non-pawns have been captured yet, or if you have already placed all of them back onto the board. My suggestion is that in such a case you win the game immediately; however, other variant is that such a move is not permitted.

A subvariant may be to combine this with other variant rules having to do with pawns, such as: Pawns can move double from any position, rather than only on their first move (and can be captured with en passan in any case it does double move). Other subvariants can be others adding additional powers to pawns, such as scorpion pawns and so on.