Muzu is a character in Breath of the Wild.
After Sidon brings Link to Zora's Domain, Link will meet with the King. King Dorephan asks Link for his assistance in helping deal with the endless water that Divine Beast Vah Ruta is pouring down on Zora's Domain. Muzu is furious after the King asks Link for help as he has strong resistance to any Hylians helping out the Zora race. Muzu is very skeptical of Hylians, due to the events 100 years ago. The Hylians abused their power of ancient civilization, which during the second Great Calamity, caused the destruction of most of Hyurule, and the dead of Mipha.
Furthermore, when King Zora offers the Zora Armor to Link, Muzu jumps in and voices his displeasure. Princess Mipha had crafted that particular piece of armor and was only to give it to somebody who she swore to marry. Muzu thinks that no such relationship existed between Mipha and Link, which would break tradition and make Link unworthy of getting the Zora Armor. Muzu will then storm off, with Sidon following shortly after with the hope to calm him down.
Divine Beast Vah Ruta
- Main article: Divine Beast Vah Ruta (Main Quest)
Muzu and Sidon will appear by the statue of Mipha, near the center of Zora's Domain. Muzu still has no desire to speak with Link, due to him being a Hylian. Sidon tries to convince Muzu that Mipha in fact had an undying love for Link. Muzu believes this to be a lie as he cannot imagine Mipha having feelings for a Hylian like him. The fact that Link is unable to remember anything solidifies Muzu's belief.
Link then gazes at Mipha's statue and it restores one of his Memories. During Mipha's Touch, Link remembers time he spent with Mipha aboard the Divine Beast, when Mipha heals Link's wounds. After Link explains that he does remember Mipha, Muzu still doesn't believe him. He thinks it's rather convenient that Link all of a sudden remembers Mipha and is not willing to change his opinion, unless there was proof. 
Sidon suggests to Link that the proof Link is looking for is the Zora Armor. He encourages Link to put the Zora Armor on and show it to Muzu. After seeing that the Zora Armor fits Link perfectly, he finally begins to understand that Link did in fact know Mipha. Muzu willt hen instruct Link to visit Ploymus Mountain, at Shatterback Point. Here Link will encounter a Lynel that shoots Shock Arrows. A single arrow could be fatal to a Zora, but Muzu instructs Link to gather at least 20 of them to appease Divine Beast Vah Ruta so he can enter.
- ↑ Now then. Hero...I must inform you that Zora's Domain is in danger of vanishing because of Divine Beast Vah Ruta. I shall do you the courtesy of speaking bluntly. We alone cannot stop this beast. Will you lend us your strength? - King Dorephan
- ↑ What?! King Dorephan! My liege! Please do not speak so! To ask a Hylian for help... Why, the very thought of it curls my fins! - Muzu
- ↑ Have you forgotten already, my king?! We cannot trust these lowly Hylians! A hundred years ago, they abused the power of an ancient civilization and turned Hyrule into what it is today! And that is not the least of it! It is their fault that Lady Mipha was lost to us... - Muzu
- ↑ King Dorephan!! Surely you do not really intend to give this outsider the Zora armor! Countless generations of Zora princesses have gifted that armor to the one they have sworn to marry! Princess Mipha made that one there with her own hands! It is far too important to entrust to a shady Hylian! He may be a Champion, but Mipha had no such relationship with him. So why should HE receive such an honor? This is just too much, my leige! I do not understand it one bit! - Muzu
- ↑ Link! Do not let his words concern you. I will work this out with Muzu. I shall return shortly! - Sidon
- ↑ Hmph. You came all the way here, but it was in vain. I have no desire to speak with you. - Muzu
- ↑ Listen well, Muzu. There is something you need to know. He who stands here...the man called Link...is the one whom my sister, Mipha, had feelings for. I was only a child then, so I did not know it myself at the time. But it is so. I grew up hearing my father tell stories, some of which were about my sister's undying love for a Hylian named Link. - Sidon
- ↑ What?! No... You cannot fool me with such a fanciful lie. Not this Zora! How could Lady Mipha possibly have feelings for a Hylian like him?! The facts are clear. He remembers nothing. Even when he looks upon Princess Mipha's statue... - Muzu
- ↑ Hm? You are quivering like a hatchling... Whatever is the matter? - Muzu
- ↑ WHAT?! Do not mistake me for a fool, Hylian! There is no way you remembered her just now, when it is most convenient. In any case, without any solid proof, I cannot possibly take you at your word! If you have any such proof, now is the time to show it. Do so, and...and I...I shall tell you how to get those shock arrows! Yes, as well as anything else you wish to know. - Muzu
- ↑ Save your lies for another Zora. Without any solid proof, I have no choice but to assume you are a lying scoundrel. If you are truly Lady Mipha's beloved, then prove it! Do so and I will tell you how to get those shock arrows, as well as anything else you wish to know. - Muzu
- ↑ The stubborn fool. Lucky for us, we have proof! Link! Go ahead and show Muzu the Zora armor my father gave you! - Sidon
- ↑ Muzu! Look closely at the clothes Link is wearing! - Sidon
- ↑ Hm? You really think changing your clothes is going to make me... Eh?! What in the... That is the Zora armor from before! Lady Mipha made that by hand... and yet it fits you perfectly! What is the meaning of this?! - Muzu
- ↑ Hmph. I never would have imagined she should make that special armor for one such as he... ... I do not approve of asking for help from a Hylian, but I suppose it is our only option at this point. I am a proud Zora. That means I must take responsibility for my unwarranted behavior toward you. As promised, I shall tell you where you can collect as many shock arrows as you will need. - Muzu
- ↑ That tall mountain over yonder... It is called Ploymus Mountain, and there you will also find Shatterback Point. A terrifying creature has made its home up there. This awful beast shoots volley after volley of shock arrows. Even a single one could be fatal to a Zora. - Muzu
- ↑ In order to appease the Divine Beast, I estimate that you will need...hmm...at least 20 shock arrows. Do you think you can gather that many? - Muzu
- ↑ If you want shock arrows, you should go to Ploymus Mountain. There resides a vicious beast there... A Lynel that is known to frequently shoot shock arrows. Though be warned... If you go, I cannot guarantee you will survive. - Muzu