Successfully complete the game, and save when prompted to create a file marked 
with a star icon. The "EX New Game" option will now appear. Start a new game 
session in "EX New Game" mode to have the Grade Shop immediately available. You 
can also purchase "Battle Rank" for 50 Grade points for an additional 
difficulty. Additionally, load your cleared saved game file to gain access to 
Nam Cobanda Isle at the northwest part of the World Map.