Radioactive Queen Chess

This variant can clearly explain the abolies of each piece in FIDE, and it's based on FIDE. So it can open new frontiers of chess & its variants.

Inspired by Manchurian Chess.

Setup

Karma strikes black back! White hasn't the Queen and minor pieces, but on the first move he/she must drop the unique piece (called Sky Brilliant, Karmium General, Radioactive Queen, Megaqueen, Cyberpiece, Superpiece, etc.; so let's call it Superpiece in this article) into any free back rank's square (so it's counted as a turn). Black is the first player to move his pieces.

Pieces

All pieces are as in FIDE except for…

Radioactive Queen

She can seem like Amazon (Terror, Maharaja, Khelgi, etc.) but it's much stronger. If Queen is heavy piece, this one is superheavy piece which can:

• as Knight: move & be placed;
• as Queen: move (incl. Pawn, Bishop, Rook, King moves) & be placed;
• as Rook: move (as Queen does) & allow King's castling to it;
• as King: move (as Queen does) & be one of the opponent's targets.

As itself, Superpiece has very strong ability. It can capture adjacent piece & move one space in any direction after this (i. e. move twice per turn but only if first move is short-range taking; second move can't be capture).

Rules

• Your aim is to checkmate opponent's King.
• If black captures Superpiece, white loses in 5 moves after this move unless black hasn't any pieces (except for Pawns) on the board BUT white has (and this is normal pawn or rook endgame); OR game ends earlier. In this case (loss of Superpiece) it ends after black's 5th move (because it can make a draw; there white loses only if result is undefined).
• Also if Superpiece is captured, and checkmating any king isn't possible, white loses.
• If white's time is over, white loses even if black can't checkmate.

Draw occurs if:

• It's stalemate.
• Black's time is over but white can't checkmate (this is only possible if white has only the king, but black's time is over before 5 moves are passed).

Other rules:

• Castling & en passant: as in FIDE rules. 
• Promotions: black promotes his/her Pawns as in FIDE; white promotes his/her Pawns only to Rooks.

Notes

Karmium is my created name for 119 element — radioactive alkali metal installed in the diamond which Superpiece carries.
There also will be the variants of

Highly Radioactive Queen

where white hasn't even Rooks, but Superpiece has hit-to-run captures on any target square, not only adjacent (in other words, it can do non-taking adjacent move after every capture); Pawns promote to non-royal Kings (Doublers); and

Radioactive Queen Mirror

where all setup, pieces & rules related to white are also related to black (with two versions: Pure RQM and light (but maybe hard for someone) version which also allows one light piece (Bishop or Knight) on any back rank's square to every player) and Pawns can promote to Rooks & Doublers (non-royal Kings), in light version - also to that light piece which player owns.

However these variations are my humble eager thoughts while main version (though preset doesn't enforce Black's winning rules) is already playable on Game Courier.

Last revised by Lev Grigoriev.