Colour Chess - 2 moves per turn, 1st move determined by opponent's move


The diagram below should give you the rough idea.

Basically if White moves to a colour, then Black must also move to that colour. They then get a 2nd turn where they can move to a different colour with a different piece, which White must then move to on the first move of their turn, etc. 

The other difference this causes is that the King is allowed to stay in check and the game is only over once he's actually captured. 

It creates the ability to force movements and lock pieces. 


If you're interested, it's up on kickstarter at the moment.