Mine (enemy)

The Cough Virus is an enemy in the Game Boy Advance game Wario Land 4. They only appear in the boss battle against Catbat in the Sapphire Passage. Two or three of these viruses are exhaled from Catbat's mouth due to a coughing fit which occurs every time Wario deals damage. They can be described as a colored ball covered in spikes with one eye and a tongue sticking out. During the first part of the battle, the Cough Viruses are purple. If Wario is to touch one, he will transform into Puffy Wario, which is of no use to the player and will merely waste valuable time. When Catbat's health gets lower as the battle goes on, the feline's cough becomes more severe, and it will send out red cough viruses instead of purple ones. These will harm Wario instead of transforming him.

The Cough Viruses trace a wavy path of movement through the air, and will continue in the direction of Catbat's exhale until they leave the screen. They cannot be truly defeated, but they will disappear immediately when Wario touches them and the relevant effect has been applied.