The Light Arrows (光の弓矢 Hikari no Kyūshi, Bow and Arrow of Light) are Zelda's and Sheik's Final Smash. When used, Zelda/Sheik draws a large bow and sets an arrow. During this time, any characters in her line of sight will flinch. A second later, the Light Arrow is released, dealing significant damage and likely KO'ing the struck characters. The move goes through walls, and when used, the match will pause as the camera does a slow-motion close-up of each hit character in order (similar to the Dragoon).
While the basic move is the same whether Zelda or Sheik uses it, there are some differences. The primary difference is that Sheik sends opponents at a semi-spike angle, while Zelda sends them at more of a 45 degree angle upwards. Sheik's Light Arrow also does slightly more damage, while Zelda's does more knockback (with Zelda's being a OHKO while Sheik's is not).
 Damage & Properties
The damage & properties of the arrow are slightly different for either character. The move can hit a maximum of 6 targets (three pairs of Ice Climbers) but the damage and knockback weaken for each target hit. Thus if used on many opponents, it may not KO the ones in the back, even at higher percentages.
The Light Arrow goes through shield and at extreme distances (the majority of the length of Hyrule Temple or New Pork City) it does slightly less damage.
Spacing is very important when using the Light Arrow. If the opponents are too close together, they may collide with each other and prevent KOs from happening. This is even more important in the Sheik version where opponents are launched at a very low angle.
 Zelda's Light Arrow
 Sheik's Light Arrow
However, these numbers can be further weakened with more targets. (i.e the Ice Climbers)
In conjunction with the Master Sword, Light Arrows have been used in the Legend of Zelda series as a weapon used to stun Ganon/Ganondorf, leaving him vulnerable to the Master Sword. The concept for them probably comes from the original NES Legend of Zelda, in which Link used a similar weapon called the Silver Arrow to defeat Ganon. Link was first able to wield the Light Arrows in The Legend of Zelda: Ocarina of Time on the N64, where he utilized them in the penultimate showdown with Ganondorf.
Light Arrows appeared again in The Legend of Zelda: The Wind Waker for the Gamecube. While Link could use them in the final dungeon, Zelda used them in the final boss battle, firing them to stun Ganondorf whilst Link strikes with his sword. In The Legend of Zelda: Twilight Princess, only Zelda can equip the Light Arrows, which she summons from the Light Spirits to help Link triumph over Ganondorf on horseback. In all of these instances, while the Light Arrows only stunned Ganondorf, they instantly destroyed other enemies in one shot. The design of the bow and the arrows is derived from Twilight Princess.
 Description from the Instruction Booklet
Fire an arrow of light that delivers heavy damage to all opponents in line with the shot. It even rips through shields.
Unleash a powerful bolt of light. The more opponents you have, the better your chances are of scoring multiple KOs in one shot.
 Trophy Description
Princess Zelda's Final Smash. She wields a mighty bow of light with which she can attack from afar. Her arrow travels in a straight line and flies through all characters unlucky enough to be in the way. This attack cannot be blocked. The more enemies there are, the higher the chances to get them all with one shot. More is always better!
Sheik's Final Smash. After grabbing a Smash Ball, Sheik will be able to wield a bow of light. The arrow fired from this bow has the power to pass through multiple targets, so it will damage all enemies in the direction it flies. This, coupled with its shield-breaking power, makes it even more terrible. Even in Sheik form, Zelda's ability as an archer is undiminished.
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