|First Appearence||Mr. Driller G|
|Latest Appearance||Mr. Driller: Drill Till You Drop|
Usagi is Ataru Hori's only companion. A small rabbit-looking creature with black-pitched fur and completely blank eyes, with no visible mouth or nose. And what is seems to be a white orb of sorts on his chest. He's able to float and shoot sparks from his ears.
He seems to understand human language, however, it'll only listen to Ataru, ignoring everyone else.
Usagi is actually an alien that came from the moon, his original plans consisted to invade earth, unfortunately for him; his ship crashed and he ended fatally wounded. Ataru happened to be near the crashing site. When he saw Usagi's unconscious body near the ship now covered in flames. Ataru decided to take Usagi with him and treat his wounds.
When Usagi woke up Ataru was already sleeping, he was planning to kill him. But Usagi noticed his wounds were bandaged by him. So he decided to change his plans and explore the world along Ataru.
Usagi has identical movement speed to Ataru and has Puchi's ability of calling two blocks at once. Usagi's main ability is drilling three blocks simultaneously with one button press: the one he's facing, and the two that are adjacent to it. Because his ability is considered one of the most useful in the series, he has the highest air consumption rate of all the drillers.
- Usagi's name is the Japanese name for rabbit.
- Usagi has been always been a quiet character, however during the ending of Mr. Driller A's arcade mode, it confirms that he speaks a weird alien language. Ataru seems to be the only one who understands him.
- Most of the methods to unlock him consist on clearing a high-difficulty level (such as North Pole or the Moon) while playing as Ataru. Additionally, he has the most unlockable appearances of any Driller in the series.