River Devil

The River Devil is a black, tree-like creature that blocks the single north-south road of Eastern Hyrule in.

Characteristics
Though citizens of Nabooru speak of the River Devil in fear, he does not attack, and serves merely as an obstruction. The only way to pass him is to play the Flute found in the Palace on the Sea.

Trivia

 * The River Devil has a much more mammalian appearance in the Japanese Famicom Disk System version of the game, being bipedal and having brown skin. Moreover, it is simply known as "the monster."