Walkers are the most common robot you will encounter. Taking only one hit to defeat, these robots should not be much of a problem on their own. However, in a group of other robots, these ones can be just as dangerous as any other robot.
Shooters do not have any interest in charging after you. Instead, it will launch an energy projectile at you, which can be a challenging obstacle to avoid.
Wheelers are one of the fastest robots you will encounter. While they only take one hit to defeat, their speed makes up for their strength. If you aren't careful enough, these robots can easily sneak up on you for an easy hit.
Towers are one of the strongest enemies you will encounter. Tower robots take 6 hits to fully destroy, and while charging at you, will occasionally tilt it's tower of heads towards you, which can be dangerous when it has a lot of heads left.
Scaredy-Bots are one of the only robots that won't chase after you. Instead, they will run away from you. If you want to destroy every robot, these ones will not be easy to take down.
Pests, like the name would imply, are small, annoying bots that are surprisingly fast. Taking two hits to defeat, Pests can be quite a challenging robot for its size.