WizKids has announced that beginning with its Mage Knight:  Dark Riders release in April, it will begin retiring previous expansions from tournament play.  Eventually this new system will extend to all of WizKids' lines; sets will remain competitive for a minimum of two years, and there will be one core set and three expansions available for tournament play at any one time.  New players will be able to participate in tournaments without collecting older, more expensive out-of-production figures.  Unrestricted events will be held each month in which competitors can use their older figures.