Spoiler What is the Execution Sword.

[ihateghirahim]

The Execution Sword is the sword used by the Sages to kill Ganondorf in TP. Later he uses it himself to battle Link. It's very powerful, and it clearly can be used for both good and evil. However we don't know anything about it. Where did it come from? Is there a connection to Ghirahim as some have suggested? What could it possibly do in the future? What are your thoughts?

 

[Shadao]

It's the Sword of the Sages, it's meant to execute dangerous criminals like Ganondorf. And like any other sword (except for the Master Sword), it can be wielded by anybody, good or evil. There's no real purpose of the Execution Sword aside from the fact it symbolizes the corruption of the light by Ganondorf's hands and the irony that a sword meant for good is used for evil.

 

[ihateghirahim]

I don't like to relegate it to such obscurity. I theorize it has a connection to how the sages were even started. They received power from the gods to battle evil, namely the lingering power of Demise and the Demons. They truly expected that blade to kill the evil Ganondorf, who we know had powerfu; magic before he got the Triforce. What if that blade is from one of the god's themselves? These events occurred after Link came back to Hyrule as a child and warned Zelda. With the Master Sword still sealed in the Temple of Time, what if the gods of Hyrule called on new sages from a new realm. These brought with them a new power This power was very powerful (I can't believe I just said that), but it was also impure It was neither light nor shadow, it was Twighlight. That is why the sages were transformed into their mysterious forms; to survive in the light of our world. That is why the sword they used could be used by both evil and good. That is why the sages were near the Twighlight portal; they came from it, and they were going to return through it. The sword is essentially the Twilight's version of the Master Sword. The sages are the Twighlight realm's version of the sages, called by the gods to protect Hyrule.

 

[felipe970421]

I don't like to relegate it to such obscurity. I theorize it has a connection to how the sages were even started. They received power from the gods to battle evil, namely the lingering power of Demise and the Demons. They truly expected that blade to kill the evil Ganondorf, who we know had powerfu; magic before he got the Triforce. What if that blade is from one of the god's themselves? These events occurred after Link came back to Hyrule as a child and warned Zelda. With the Master Sword still sealed in the Temple of Time, what if the gods of Hyrule called on new sages from a new realm. These brought with them a new power This power was very powerful (I can't believe I just said that), but it was also impure It was neither light nor shadow, it was Twighlight. That is why the sages were transformed into their mysterious forms; to survive in the light of our world. That is why the sword they used could be used by both evil and good. That is why the sages were near the Twighlight portal; they came from it, and they were going to return through it. The sword is essentially the Twilight's version of the Master Sword. The sages are the Twighlight realm's version of the sages, called by the gods to protect Hyrule.

This is somewhat lacking evidence, I'm afraid there isn't much in game about the sword, but for future reference, take a loot at the actual blade (from HH concept art)

And the final sword

The sheath is particularly interesting, the blade itself is clearly meant for the sages, but the sheath is clearly Ganon's handiwork.

 

[Ronin]

Interesting that you should mentioned this; it's actually the first time I've noticed Ganon had fought Link with the Execution Sword, the very weapon that the Sages tried to kill him with. But yeah, it's really just a blade which the Sages used for execution when they banished prisoners to the Twilight Realm [hypothetical, but as they did with Ganondorf], and Ganon stole it from them.

On a side-thought, does anyone think there's any correlation between the Execution Sword and Death Sword's blade?

 

[Justac00lguy]

The sword itself was owned by the sages and was used for the sole purpose of executing evil beings within the Arbiter Grounds. However the fact that the sword itself is actually really powerful as was able to with one thrust, severely injure Ganondorf and the fact that he takes it himself as well as it being able to cope with the Master Sword itself makes me wonder if the blade is something more...

However I was thinking about the subject and this sword is actually the "Sword of Light" and it seems to follow suit of the light spirits in TP so maybe it has the same divine power as the light arrows Zelda summons. Also the fact that Ganondorf used it was in my opinion to get revenge on the sages themselves, this quote was said in the final battle with Ganondorf.

An impressive-looking blade... But nothing more. Would you hear my desire? To take this foul blade...and use it to blot out the light forever!- Ganondorf

Now in my opinion I think Ganondorf decided to use this blade in the irony of what it is supposed to do and he wants to use it to blot out light so the sages can see what damage has been done with their own blade.