Introducing a new chess piece -- the Wuss. The Wuss moves exactly like a Queen, except:
  (1) it cannot capture, and
  (2) it must move when attacked.
 
The attack cannot be blocked and the attacking piece cannot be captured. Win by capturing the opponent King or Wuss. If a Wuss is attacked and has no move, that player loses. White cannot open with a Knight move. Normal chess rules otherwise apply.
 
The Wuss is a powerful piece - for the opponent. Attacking the Wuss provides a (nearly) risk-free way of developing your forces. The opponent is helpless as long as you keep attacking the Wuss, and in the process you can bring out your pieces. The Wuss is particularly dangerous to its King. A loss will automatically follow when both the King and the Wuss are attacked on the same turn.
 
In Wuss II, the player has a Wuss in addition to the regular 16 pieces. In Wuss III, the Wuss replaces the King and moves like the King. In Wuss IV, the Wuss has the combined moves of the Queen and Knight.