Squee-G (Suckerfish in the European version of Splatoon) are Octarian-made machines that appear in Octo Valley, Octo Canyon, and the Octo Expansion. They cannot harm the player, instead serving to hinder progress by removing their ink. However in Splatoon 2, there is a giant version of the Squee-G that is able to harm the player and Octarians.
Squee-Gs are small, fish-like robots attached to a surface, either on the ground or a wall. When this surface is inked, they automatically move to clean it up while making squeaking sounds. They cannot be destroyed, but are momentarily slowed down when shot at or stood on. Their eyes, fins, and mouths are a light teal when idle and turn yellow when they spot ink.
Pickups such as Power Eggs or Armor can sometimes be found on their backs.
In Splatoon 2, there is a larger version of the Squee-G. This type of Squee-G is very dangerous, as if it runs into the player, it instantly breaks Agent 4's armor. It can also instantly kill Octotroopers, even Shielded Octotroopers. They also outrun Agent 4, so be very careful when dealing with a giant Squee-G.