Digdogger

Digdoggers are a species of giant cycloptic sea urchin, specifically based on the Unira enemy from the game . While slow, they deal a large amount of damage on contact and are invulnerable to normal attacks. However, shockwaves cause them to shrivel up into a small and vulnerable, but fast and still hard-hitting form called mini-Digdoggers, often split into many.

The Legend of Zelda
In The Legend of Zelda, a Digdogger first appears as the boss of the 5th labyrinth, Lizard. The Digdogger itself can only slowly move around its room, with most of the immediate danger coming from Stone Statues found in the corners. Reaching it is fairly simple, but Link cannot deal any damage at all to it until he gains the Recorder, requiring him to take an alternate path full of blue Darknuts. Once Link gains the Recorder and plays it before the Digdogger, it shrivels into a small version of itself which starts ricocheting around the room erratically to flee from Link. After a few hits, however, it is defeated. Later, three Digdoggers appear as generic enemies in various rooms of the seventh labyrinth, Demon. They work the same as the first one, but split into three small versions instead of just shrinking into one.

In the Second Quest, Digdoggers first appear in Level-4, where one is an enemy early on and another is a boss. Later, two appear as enemies in Level-8. All of these Digdoggers split into three.

The Legend of Zelda: Oracle of Seasons
In The Legend of Zelda: Oracle of Seasons, a Digdogger appears as the boss of the fifth dungeon, Unicorn's Cave. It is more proactive in attacking Link than the ones in the first game, hopping around the room to hit him. Occasionally, it jumps so high it goes off the screen and then slams down near Link, taking a moment to recover. To damage it, Link needs to use the Magnetic Gloves to pull a giant spiked ball off a pillar in the corner and move it into Digdogger. After a few hits from it, Digdogger will split into six mini-Digdoggers, which frantically run around the room. They can be beaten with normal weapons or flattened with the ball, but when only one remains, it grows back into a full-sized Digdogger. It must be hit with the ball again a few more times, causing it to shrink back down, letting Link defeat it. Once it is defeated, Link gains the Nurturing Warmth.

BS Zelda no Densestu
In BS Zelda no Densetsu, Digdoggers act the same as in the first game, but always split into three. Additionally, since the Recorder has been replaced with the Ocarina, they are now weak to that. One first appears as the boss of Level-4, where the Ocarina is, and another appears as an enemy in Level-6.