Zero and 18.

Zeroids are the footsoldiers of the Terrahawks. They are spherical, sentient robots about the size of an adult human head, each equipped with a laser and radio links to each other. They are also shown to be extremely resilient, able to survive huge drops from ships such as the Battlehawk and able to break through almost anything by increasing their mass by building up momentum through sustained rolling. Indeed, the only thing shown to destroy one was a focused blast from one of Zelda's ships. At least 202 are shown to exist, both on earth and in space.

101 Zeroids exist in space operating from Spacehawk as the ship's weapons, while 101 more exist in Terrahawks HQ. This often leads to bickering between Space Sergeant 101 and Sergeant Major Zero over who has more authority when the two come together. A number of Zeroids are shown to have distinct personalities, such as the jive-talking 55, the French-accented 18 and the Scottish-accented 66. Zeroids can be seen as the series' mascots, and appear in the credits for every episode, playing tic-tac-toe against Zelda's Cubes.