Digdogger (The Legend of Zelda)

Digdogger is invulnerable to all of Link's attack until Link plays the whistle, found in Digdogger's own Level 5 in the First Quest and in Level 2 of the Second Quest. Playing the whistle shrinks Digdogger and makes it assailable. When the creature appears as a boss, it can then be killed simply by a few sword swipes or with bombs. When it features as a mini-boss, however, after one slash (or bomb) it will split into three mini-Digdoggers, which must each be killed separately (again, with either the sword or bombs). Fortunately, the three parts can never reform the original Digdogger. This oddly means that this enemy is more difficult when it is not a boss.

Digdogger can damage Link by simply making contact with him (as can the mini-Digdoggers), but this is its only attack. However, most Digdogger rooms also contain statues in the four corners which can attack Link by shooting fireballs at him. Digdogger is immune to these fireballs in all forms.