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Head north and kill the boomerang bears. When they are all dead theBoomerang will appear. Grab it. Head north and grab the Compass. Continue north. Kill the Stalfos (one drops aKey) and head north through the locked door. Kill the Gels, grab the Map, and head east.

Bomb the southern face and head south. Grab the Bombs and continue south for three screens. Push the left-hand corner of the diamond down and go down the stairs. Kill the snakes and bomb the eastern face. Head through to fight the boss, Dodongo.

To defeat Dodongo, place bombs right in front of its face. It should then walk onto the bomb, eat it, and take damage. Alternately, just walk right up to him and place the bomb onto his body and it should end up in his stomach anyway. Collect the Heart Container and head north. Grab the Triforce piece and you're done.