Kirby Super Star has a few abilities that are used in speedruns. Most abilities are completely disregarded in favor of abilities that prioritize speed and damage.

Jet

Jet is the most common ability in KSS speedruns. It is used throughout the entirety of Dyna Blade, Milky Way Wishes Any%, and most of Revenge of Meta Knight. Jet is one of the best moves for horizontal movement, and is best applied when chained sequentially in the air. Jet is also great at moving up vertically by using its hover, which is faster than Kirby's standard hovering.

Wheelie Rider