Giant Buzz Blob

The Giant Buzz Blob is the first mini-boss of the Color Dungeon, which can be found in Link's Awakening DX. This boss is comparable to a regular Buzz Blob but is much larger and more formidable. Upon his defeat, the Giant Buzz Blob will drop a Nightmare Key.

Strategy
To defeat the Giant Buzz Blob, Link must sprinkle Magic Powder upon him. Once done, he must be struck with the sword. Throughout the battle, Giant Buzz Blob will shoot lightning bolts which the young hero must avoid.

Trivia

 * The Giant Buzz Blob shares similarities with the Big Blue Chuchu from The Minish Cap.