Diamond is designed for pro gaming purposes. It has tighter gameplay than original Forged Alliance so map control is more important. There are less shortcuts to victory so you have to really dominate your opponent to get a win. Fixes also most of the bugs found in game. You can now use every tactic, unit or acu upgrade found in game without being labeled as "insert method here" noob. Of course haxing and glitching is not allowed (offmapping etc.)