Bilocyte

Ocular Parasite Bilocyte is a boss in The Legend of Zelda: Skyward Sword. It is encountered on the enormous whale-like creature Levias. It fires noxious goo from its eye stalk, but Link can repel the attack with his sword to launch it back. In order to get in an attack against its central eye, however, Link has to deal with the fins on either side. By swinging his sword to the left or right, he can send back its goo attacks at different angles in order to direct them at the fins. Once the fins are destroyed, vertical sword strikes are used to send the balls of gunk back to the eye.