Pieces move as usual, but they all hide a special "power"
inspired by Mario Kart:
The pawn (Toad) leaves a "turbo" mushroom on its initial square,
or on the intermediate one in case of a two squares move.
The knight (Yoshi) let a surprise egg on its initial square.
See about egg effect below.
The rook (Donkey) put a banana on a square diagonally adjacent to the
arrival one, at random, if possible.
The bishop (Wario) put a bomb on a square orthogonally adjacent to the
arrival one, at random, if possible.
The queen (Mario) can play a stealth move once in the game:
the opponent will only know that a queen moved - to an empty square.
A promoted queen also has this power if not already used.
The king (Peach) can "throw a shell" on an enemy reachable by a queen,
once in the game. A promoted king also has this power, if not already
used. The capture is done remotely without moving.
The king cannot castle, and pawns don't capture en passant.
So the goal is to capture Peach :) If pawns promoted into king, then all
of them must be captured. Since it still looked too easy, the 4 mentioned
objects alter the move played, generally at random:
A king or a pawn arriving on a mushroom advance one square further,
while a knight jump another time in the same direction, if possible.
Pawns can "eat" objects diagonally too.
Mushrooms have no effect on sliders (queen, rook, bishop).
A piece arriving on a banana (resp. bomb) is redirected at random by one
square in an orthogonal (resp. diagonal) direction. If a piece (of any
color!) stands on that square, then it is captured.
The effects can cumulate, as illustrated on the diagram: the pawn
"captures" the banana on e4, and is then redirected toward e5: mushroom,
it jumps to the next square, which sends it on d5 eating the white rook.
(We can imagine that the hope was to eat the black knight instead).
A piece may ends on its initial square, move back, and so on. That being
said, a given object can only be used once on the path.
The egg case is more complex: a move ending on an egg triggers an effect
chosen at random, positive or negative. There are four bonus and four
penalties. They are introduced in a dual form: first the positive, then
the negative.
King Boo (*B) let you exchange the position of any pair of pieces on the
board.
Koopa (*K) drives the piece back onto its initial square.
Toadette (*T) allows to place a new — random — piece on the
board. If the piece is dropped on an egg, banana or bomb, its effects
are applied.
Chomp (*C) eats the piece, which is thus captured. If it's Peach, then
bad luck, game over :)
Daisy (*D) allows to play again with any of your pieces.
Bowser (*M) immobilizes the piece (which is surrounded by a light green
halo). It won't be allowed to move on the next turn.
Luigi (*L) changes the color of a random enemy piece.
Waluigi (*W) changes the color of one of your pieces (at random).