Robbie Baldwin's exposure to energy from a dimension of kinetic energy gave him the superhuman ability to create a kinetic field of unknown energy around himself which absorbs all kinetic energy directed against him (what he originally called the "Speedball Effect.") This absorption can vary from resisting the effects of physical objects such as bricks and rocks to resisting that of energy and fire and even explosions. Within his kinetic field it is nearly impossible for him to be hurt, and he instead bounces harmlessly from object to object, with no loss or transference of momentum.
When transformed into Speedball, he was covered with a blue-and-gold costume (originally a facsimile of the lab uniform he wore when exposed to the energy) and surrounded by a display of multi-colored bubbles. At first, Robbie would transform uncontrollably if hit with a slight force and bounce around uncontrollably, making him originally seen as a "joke" character. However, in his years as a member of the New Warriors, he developed considerably. He gained the ability to manipulate his kinetic field to extend out to either attack an enemy or block a projectile. He typically used the field to slam into his opponents, and the multi-colored light display can be used to distract opponents. After many years, Robbie learned to extend the kinetic field outward, pushing back everything in his immediate area or, by focusing more locally, delivering more powerful blows in hand-to-hand combat. His "bubbles" could also be contained in a telekinetic field (see: Justice) and then launched as an intense attack. Later, Robbie would also discover that his entire body was in fact an aspect of the "kinetic dimension," and that each bubble represented a moment in time.