The patch for Crusader Kings II
will release alongside new DLC that enables players to rule as Muslim rulers, with a wealth of new mechanics based around these rulers. Marriage, laws, traits, and titles will all be taken into account, and the map will be expanded in to Mali-Songhay.
Patch 1.06 will add new features such as expanded combat, new plot points, differentiation on strong and weak claims, and new locales.
The new patch and the Sword of Islam DLC will release in June.