Hop Chess

0. Same as FIDE except:
1. On each turn, each player must do both the following actions:
   1.1. Move a friendly chess piece; then
   1.2. Move his hopper to any empty square
2. If a chess piece moves onto a hopper (of either color),
    it must move  again (it's invalid to return to the initial square).
   2.1. Kings cannot move onto a hopper, nor castle across one.
   2.2. If the piece cannot move after the hopper, the move is invalid.
   2.3. If a queen lands on a hopper, it continues with the same type of
    movement that it used to get there (ie, both orthogonal or
    both diagonal moves).
   2.4. En-passant is still possible, but not if either pawn moves twice
3. Initially, the hoppers start off-board.
   White's first move is restricted to a piece move only.
  
Notes
  
* When moving the hopper, the player may place it where it was.
  He does not have to change the place of his hopper every turn.
* Pieces may move over hoppers.
* A piece may execute two hops, if it moves from one hopper to another.
* A hopper extends the moving/capturing range of pieces,
  so a King may be under check via one or both hoppers.
* It is not possible to capture more than one piece per move,
  since hoppers are always on empty squares.
* A pawn may promote onto a hopper and then the player must move
  the promoted piece.

Example   (@ white hopper, # black hopper)

r . b q k b n r    Some valid moves:
p p . . p p p p     Bc8-f5-e4
. . n p . . . .     d2-d4:c5
. . p . . # . .     Nc6-d4-f5:g3
. . . @ . . . .
. . . . . . O .
O O O O O O B O
R N B Q K . N R

A game:

HOP-CHESS
=========
 1. e4         Nf6  d5
 2. d4   d3    e6   b4+  
 3. Nc3  g5    Be7  b4  
 4. B:f6 e5    e:d4 b4    
 5. Q:d4 e5    g:f6 b4    
 6. e:f6 e4    Na6  c5    
 7. f:e7 d5    c:d4 b4    
 8. e:Q+ f3    K:Q  e8+
 9. Nce2 f3    d3   b4    
10. c:d3 c1    Nd4+ e8    
11. Kd2  h3    N:b2 c4+
12. Kc2  a4    Na3+ e6
13. Kb3  c1    Re5  a5
14. Ne4  c6+   Ke8  e3+
15. N:e5 c6    a5   a4+
16. K:a3 b1    b5   b4+
17. B:b5 e1    resign

r . b . k . . .
. . . p . p . p
. . . . . . . .
p B . . N . . .
. # . . . . . .
K . . . . . . .
O . . . . O O O
R . . . @ . N R

Even though the existence of hoppers makes the opening and middle game much more attack-oriented, and also the distant endgame, it dies NOT seem to be the case for most K & P endgames, even with a minor piece or two.  The reason is, that the weaker side can use his hopper to stop the stronger king from ever making a breakthrough into the enemy area, as usually happens in endgames.  So there are SOME games at least that are harder to win in the hopper version. But not many.