In what amounts to a relatively small walker, a few users have created sketchyphysics "infantry" who function as footsoldiers in the otherwise tank-dominated sketchyphysics military set of models. While laggy and complex, they are often quite fun.
The infantry models saw their birth in Sketchyphysics3. A user known as Platypus5 was one of the first users to start making infantry models, and gradually more specialized users such as orandif started as well. Eventually, other users caught on as well, making their own styles. However, it remains a relatively unpopular model type, due to the lack of progress that has been made in this region of sp technology.