The yo-yo glitch refers to a glitch in Super Smash Bros. Melee done using Ness's yo-yo. It can be used to attack or grab with near limitless range or attach certain single-hitbox attacks to Ness's body. The discovery of the glitch was a collaborative effort between VilNess, LonelyNess, and Dan Smith, and was spurred on by an innocuous video of an unknown Japanese player accidentally dropping a yo-yo hitbox.
The glitch can be performed in all versions of Melee.
Ness's up smash consists of 3 parts each with its own hitbox: outreaching, spinning, and swinging. The yo-yo glitch drops the last hitbox of the up smash onto the ground and leaves it there until Ness gets KO'd or uses a non-projectile attack.
How to perform it
Perform the Yoyo Glitch. Use PK Thunder to floorblast yourself from the air or use PK Thunder to hit yourself into a ledge and grab it. Effects:
Attaches the hitbox of PK Thunder (Ness' recovery attack) to Ness' body. Blocks most attacks that it collides with and hurts opponents and destructible stages.
Perform the Yoyo Glitch. Use D-air and land immediately after the hitbox comes out. This can be done by Short hop fast fall l-canceling. Effects:
Attaches the hitbox of Ness' D-air to his lower body. Meteor smashes opponents and hurts destructible stages.
Perform the Yoyo Glitch. Use U-air and land immediately after the hitbox comes out. This can be done by Double jump canceling. Effects:
Attaches the hitbox of Ness' U-air to his upper body. Pops up opponents and hurts destructible stages.
Perform the Yoyo Glitch Use up smash or down smash on a disappearing platform timed so the platform disappears right as the yoyo comes out. This can be done on the awnings in Onett. Effects:
Attaches hitbox of Ness' up smash or down smash to his feet. Causes either weak or strong yoyo knockback based on the timing of the setup.
Perform the Yoyo Glitch. Be inhaled and spit out by Kirby Effects:
Attaches the hitbox of Kirby's star launch to Ness' lower body.
Perform the Yoyo Glitch. Have another character use a normal throw on Ness into a wall or ceiling. Effects:
Attaches the hitbox from a throw to Ness' body. This is a unique way to get the Dead-Weight KO bonus.
Perform the Yoyo Glitch. Use any non-projectile attack or a grab and that attack will hit every target in between Ness and the location the Yoyo Glitch was performed (if a grab is used then only the target closest to Ness will be affected). Effects:
Adds near-limitless range to Ness' attacks.
After using the yoyo glitch, certain other attacks can be used to replace the yoyo hitbox with the hitbox of the attack used. The rules of the regular yo-yo glitch still apply when using a jacket.
If any non-projectile attack other than the ones listed is used to hit all targets between Ness and the location this glitch was performed, the jacket will be transferred to the opponent, allowing for near-limitless range.
Super Yo-yo Glitch
It is a very rare occurrence, so very little about it is known. Its effects (including but not limited to infinite Jackets and instant KO throws) are similar to those of the Yoyo Glitch, but are more lethal and have longer lasting effects.
Most Ness mains don't believe in it's existence due to little evidence.
This technique holds much value to Ness players and is said to be the secret to beating the Bowser Challenge.