How found: Go to North Clock Town on midnight of the first day and wait until the old lady from the Bomb Shop enters. A thief will knock her down and run off with her bag, give chase and hit him with your sword to make him drop the bag. Once the thief leaves the screen, the old lady will reward you with the Blast Mask.

    How used: Press B to detonate the mask, damaging everything close to Link as well as Link himself. The mask must recharge for a few seconds before it can be used again.