Press ↓+A to perform a Slide attack. You can do this even when you have no ability equipped!
— Attack with Slide! • Kirby Star Allies loading screen

Slide (also slide tackle or slide attack) is one of the most basic moves in the Kirby series and can be used by a multitude of characters, such as Kirby, GooeyMeta Knight, King Dedede, Bandana Waddle Dee, Shadow Kirby, or any of the playable helper characters in Kirby Super Star, Kirby Super Star Ultra, and Kirby Star Allies. The character using this move slides along the ground with one of their legs sticking forward to kick any enemy or Star Blocks in the way. Some characters may also use different body parts or weapons for this such as Birdon's beak or Blade Knight's sword. It does little damage, but can defeat some weaker enemies in one hit. In essence, if Kirby has no power available and needs to deal fast damage to a foe, the slide attack is better than nothing.

Kirby can use it to attack enemies that he can't inhale like Scarfy. It can also be used to get under places, quickly destroy blocks, or for use as an attack, as mentioned before. The slide attack doesn't work on mid-bosses and bosses, as it is too weak to dent them; it will push Kirby back instead, and he will get hurt. However, it is capable of dealing light damage to other Kirbys in Kirby Fighters and Kirby Fighters Deluxe.