If a player executes an initial dash (including foxtrot or dash dance) or a run turnaround into Crownerang while the move is active, King K. Rool will "slide" while picking it up. Crown sliding has seen significant use in competitive play. Onua is a particularly prolific user in high level play. The technique has multiple variants that can be executed based on the inputs used by the K. Rool player.
Regular Crown Slide
The regular Crown Slide is executed through executing a run turnaround when close to the crown. This will have K. Rool go a long distance with his back turned.
Crown sliding is usually used for enabling combos from Crownerang, such as Crown Slide into grab at 0% (thereby allowing for forward throw to dash attack) or an early up tilt at low to mid percentages. Outside of this, however, it is mostly frame traps. Crown Sliding is also somewhat useful movement option in niche scenarios, being able to be used as a mixup option for getting around the stage or catching opponents off-guard. The short lag period leaves K. Rool a bit vulnerable however, making its usage debatable when approaching.
Crown sliding has various issues, however. The lag of the crown catch animation means that during the slide, K. Rool is completely vulnerable. While 17 frames of lag is less than airdodge landing lag (which is 19 if perfect), being almost always forced to go forward means that K. Rool is often catapulting himself into attacks if it's executed rashly. Leaving K. Rool with his back turned also tends to cause him trouble, forcing players to pivot afterwards or commit to stay facing forward. As such, the regular variant of the slide rarely sees competitive use.
Forward Crown Slide
By using the C-Stick in the opposite direction at the same time as the control stick input, it's possible for K. Rool to go a boosted distance while also facing forward. This functions as a niche approach option akin to a wavedash, though reckless use often leads to a punish. While it has little to no combo utility, its use as an extra boost in movement gives K. Rool extra options for mixups or simply pursuing opponents. Since the FAF of a Crown Catch is just 18, it is possible to attack while sliding, or cancel momentum with some attacks, giving K. Rool some approaches akin to pivot cancels.
Reverse Crown Slide
It is possible to reverse a crown slide through inputting the opposite direction right after doing the normal input. In this scenario, K. Rool will do a quick double-pivot. This is known as a Reverse Crown Slide. This is made far easier with the C-Stick, although it is not required. If inputted correctly, King K. Rool will slide back roughly the length of his character backwards. The slide's spacing has shown itself to be useful for microspacing, mindgames and reads, with Chad being a common abuser.
Reverse crown slide enables his neutral attack as a true combo at 0% for 33.6% in 1v1, while also generating a tech situation. This is more consistent than a normal crown slide, while keeping the combo moving forward, allowing for more utility in advantage state. As a result, it is very possible to deal an upwards of 50% out of the gate abusing this tech and the situations Jab provides. Forward tilt and forward smash are also possible out of this, but they are generally considered to be suboptimal due to inconsistencies. This can also be used for a down tilt aerial hitbox, forward tilt and up tilt on all variants of the slide.
While safer than a regular crown slide, reverse crown slide has some issues. It is possible to execute the forward crown slide if the c-stick and control stick are pressed together, which has K. Rool catapult forward. As such, it's possible to get the opposite of the desired result should the player be too rash. If done too late, the double-pivot effect will also worsen in momentum, thereby making the spacing go from minimal to none at all. Practice is necessary should a player make use of the technique.
Initial Dash Crown Slide
If an initial dash crown cancel is executed too early or too late, K. Rool will execute a slight crown slide instead. This has niche use with neutral attack as an approach, or a mixup with grab, but it generally doesn't excel due to how short the slide is. This crown slide is also the only way for K. Rool to go completely backwards; through initial dashing the other way (which also moves the catch searchbox). However, the precision required often makes it inferior to the reverse crown slide. In addition, the slide is often negligible if not executed properly.