Four Swords Progress
Silver Keys: complete each level with a team score of 1000 or more Rupees, then beat Vaati for ending #1.
Gold Keys: complete each level with a team score of 3000 or more Rupees, then beat Vaati for ending #2.
Hero Keys: complete each level with a team score of 5000 or more Rupees, then beat Vaati for ending #3.
Riddle Quest
Obtain ten medals and you can start a riddle quest with the Lumberjack in Link to the Past. Complete the Riddle Quest to obtain the Hurricane Blade special move.
Unlock Sword Beam
Play A Link to the Past and get the Master Sword and save.