Zap Jump
Zap Jump is an advanced technique that can be used by Lucas. It was discovered by Christopher Daniel Winans, making it possible to double Lucas's second jump.
To execute this boost, you must use PK Fire within one frame of your double jump. The timing takes a bit of practice, but if you hit the special-moves button right only slightly after executing your jump (essentially hitting them at the same time), Lucas will shoot up quite a long distance. The PK Fire's lag will be almost reduced to 0 due to the great jump he makes. This can be combined with Lucas' other techniques such as B-Sticking and Magnet Pull for an impressive recovery. To make the execution of this technique easier, it is advised to set the L-button (or R-button if you roll with the L-button) to jump, so you do not have to claw the L and B buttons at the same time.
PK Jump
There is also an interesting effect when Ness' PK Fire interacts with his second jump. When PK Fire is executed at the same time as his second jump, he shoots forwards and up a bit while using his PK Fire. It makes a great approach and it extends PK Fire's range greatly. It can also be used as recovery. While it is not as long as Ness' second jump, the PK Fire acts as a barrier against any opponents trying to edgeguard from below.
A variation of this maneuver, known as the Firebound, combines the mechanics of the PK Jump and B-Sticking. If you tilt the B-stick backwards while holding forwards and double jumping, you will shoot backwards and slightly. This is used as a defensive move compared to the PK Jump's use for attack.
How it works
Members of Smashboards have discovered why this happens. Normally on Lucas's second jump, an upward force propels him upwards, like most characters, but the ascent is hindered by a downward force right after this. PK Fire somehow cancels the downward force, causing a huge, fast jump.
Videos
Lucas' Zap Jump
<youtube>2q7RqH1Lfu4</youtube>
Ness' PK Jump
<youtube>8QHePOJRNKE</youtube>
Lucas' Advanced techniques (Zap Jump is first one shown)
<youtube>oGjNswHpHGU</youtube>