In most regions the Six Button Control Pad was released with Street Fighter II: Special Champion Edition which made use of the six-button layout. Though the game had been released on the Super NES, it had to assign moves to the L and R buttons - the Mega Drive version is therefore more analogous to the original arcade version (and also means a separate arcade stick does not necessarily need to be purchased). Some games do not function with the six button controller. To fix this situation, Sega added a Mode button on the top right of the controller. If held while the system is booting, the controller will revert back to a three button pad. Many six button games make use of the Mode button within play, bringing the total number of buttons to eight (plus a D-Pad). The Super NES also has eight buttons, meaning porting games between the two consoles was made much easier.