Guttertanks are Greater Machines that are first introduced in the 2nd level of Layer 7, also An Enemy from ULTRAKILL.
The Guttertank primarily attacks by firing rockets at the person, which if missed, freeze upon getting close and explode after a short duration. These rockets function largely the same as a Person's primary fire Rocket Launcher, including how magnets attract rockets. Occasionally, it may lay down a landmine in its current location instead of firing a rocket. 