William Massachusetts

"Meetings are boring and useless. I want to walk my own path!"

- William, Volume 2 Annex

William Massachusetts, also known as Mithril Eyes William, is an Elf Assassin-Hunter and the guild master of Silver Sword.

As the guild master of a raiding guild, William held that whatever happened to the city, for good or ill, was not his concern. In the wake of the formation of the Round Table Alliance, and the good it brought to the city, he goes into self-exile with his guild following him. While Adventurers speculated that William was too proud to bow down to any kind of governing body, the truth was that his decision was brought on by a feeling of shame due to his own pettiness.

When Shiroe ventures north to the Depths of Palm, William readily agrees to volunteer himself and his guild to aid in his latest scheme to make up for his previous lapse. By this point, they had ended up in Susukino, taking over the city by ousting the tyrannical reign of Brigandia.

In volume 12, he and Silver Sword join the New Round Table Council, bridging Susukino and Akiba together.

In the real world, William is a high-school student whose real name is Masashi Nakayama (中山雅史).

Appearance
While William is noted to have the handsome looks of a young prince, his short-temper contrasts with that image. In the light novel, he was stated to have silver hair, but it was changed to blonde in the anime and the light novel illustrations thereafter, although the light novel text still says that he has silver hair.

Although his eyebrows are usually furrowed, he isn't usually angry and is instead just burdened by the responsibilities of leading a raiding guild.

Personality
William's first impression is that of a proud, uncompromising, and impatient man. He decided not to sit in on the Round Table Conference discussion, preferring to "walk his own path." However, he encourages the remaining eleven guilds to work on the current problem, proving that he's against joining the alliance but not against their principles.

William's pride &mdash; and by extension, his guild's &mdash; led them to oust Brigandia's rule over Susukino. In their eyes, true worth was found in tackling difficult raids, and people who picked on those weaker than them were lower than trash. It is implied that William defeated Demiqas in a duel, which has led the man to become obedient once it comes to William's orders.

Shiroe notes that William is charismatic, able to rally the Abyssal Shaft Raid Party even though the situation seemed hopeless, and thinks to himself that he wouldn't be able to do such a thing. In notes on the raid party, William is stated to have become Silver Sword's spiritual support.

He later reveals that he held animosity towards the Debauchery Tea Party, having idolized them when he was a younger player and hoping to join their group once he reached level 90; however, by the time he finally hit level 90, they had already dissolved without even a trace of their former glory, forming a sense of betrayal within him.

It is revealed that in the real world, William was a serious gamer who had difficulties communicating with and befriending his classmates, which is why he was so engrossed with playing Elder Tale.

Before the Catastrophe
When he first began playing, William heard of a legendary party that took on raids all over the world, and sought to join their ranks. However, by the time he was at a level high enough to join, it had disbanded without even a guild to leave its legacy, producing animosity within him since they "didn't wait for him." As a result, he formed Silver Sword to take on raids both local and overseas to create the same legacy the Tea Party had. Most of its members, like himself, weren't very good at communicating with others in the real world, but made very good raiders. William despised the people who told him to get a "better hobby" or belittled him for playing Elder Tale.

In the real world, William is a high school student who lives near the Hitachino-Ushiku Station in the Ibaraki Prefecture. He does well in English class. Along with Elder Tale, William also likes Legolas.

The Catastrophe arc
William was seen rallying his guild right after the Catastrophe.

Round Table Alliance arc
William appears at the beginning of the episode as Shiroe explains how guilds work. Silver Sword is mentioned by Marielle as one of the guilds that was aiming to reach level 91 along with the Black Sword Knights.

William is one one of the guild masters who is invited to the Round Table Conference escorted by his elite bodyguards. However, he leaves shortly after the conference begins, because he feels that the situation in Akiba isn't something that his guild, which is a combat guild, should care about. Even though he doesn't personally want to be involved in improving the conditions in Akiba, he encourages the remaining guilds to continue working on the problem in his absence; he is against the Silver Sword's participation, not against the idea in principle.

Libra Festival arc
William appears at the very end of episode 25, approaching Demiqas after he and his guild reached Susukino in their self-exile from Akiba.

Gold of the Kunie arc
Shiroe, Naotsugu, and Li Gan head to Susukino, where Shiroe requests Silver Sword's participation in a new Raid Quest at the Depths of Palm. Although William accepts Shiroe's request and is willing to listen to the former Tea Party counselor's assessment of the new raid content, his primary concern was that his guild no longer had the motivation to go on raids, so he probably could not recruit enough people to go on even a Full Raid. As Shiroe met with William, Demiqas barges in, still bearing hatred towards Shiroe and Nyanta for his defeat several months prior. Although Demiqas threatens Shiroe, William tells Demiqas to back down or he'll "kick [Demiqas'] ass again," causing Shiroe to infer that the two had dueled, with William winning overwhelmingly. William manages to rope Demiqas into assisting in the Abyssal Shaft raid, much to the latter's annoyance, upon seeing the arrival of Naotsugu and Tetora.

Despite the large distance between the Depths of Palm and Susukino, William decides to travel the route by foot, a decision that Shiroe honors and has his group (himself, Naotsugu, Demiqas, Tetora, and two Silver Sword members) do likewise. Several days into the raid, both William and Shiroe noticed that the raid was much more difficult than they had expected and worry that their supplies would run out. In particular, the materials needed to repair their equipment (and for William, creating more arrows) would be in short supply.

On Christmas Eve, the Raid Party reaches Luseat, the third raid boss of the dungeon. After difficulties fighting Luseat, they are ambushed by two other raid bosses—Taltaugar and Ibrahabara—in a previously-unthinkable scenario. As William falls to his knees, he wonders if this raid was designed to be impossible before Ibrahabara incinerates him.

Upon revival, William listens to the laments of his guild mates, who wonder if the other raid zones will have similar traps to what they had just suffered, and if they should just quit raiding and be a peacekeeping guild in Susukino. This spurs William to rally his guild and open up to them, declaring his love for raiding and for Elder Tale, and telling his guild mates that they are the only people he was ever able to connect with on a personal level. He also opens up about why he had accepted Shiroe's request for his participation in this raid: that he had run once from Akiba when he was needed, and that Shiroe had succeeded in a "raid" which created a bustling city. This inspires Silver Sword's rank and file to rise once more and try again.

With Shiroe's new strategy in motion, William participates in the plan to take on both Ibahabara and Taltaugar in the former's cave. After great difficulty, the raid party succeeds in defeating both raid bosses, and William decides to give some of the rewards to Shiroe. When Prometheus plants the Silver Sword flag in the ground, William proudly declares that Silver Sword are the first Adventurers to have cleared this raid zone.

When Shiroe returns to Akiba, William requests Shiroe add him to his friend list, only to find out Shiroe had already done so.

Noosphere arc
During the attack of the Eternal Moths, William leads his guild in protecting Susukino from them and coordinates the defense of Akiba. After the Shibuya Raid Team successfully clears the raid, Shiroe informs William afterwards about the new raid dungeon.

Collapse of the Round Table arc
At the end of the volume, William goes through Susukino's Transport Gate on his griffon mount to demonstrate the newly re-operational gates in Susukino and Akiba as part of the plan to garner support for the New Round Table Council with Raynesia as representative in lieu of the missing Krusty. During Raynesia and Shiroe's speech on behalf of the reformed Round Table Council, William is revealed to be joining as the representative for Silver Sword, which was now joining the new Council.

Nightingale's Song arc
William, Dinclon, and Enkaatanto are present in Akiba when Eirenus turns the city into a raid zone, and find themselves in danger when Eirenus forcibly reduces their levels to 35 through its abuse of the Teacher System. They meet up with Rieze and are able to gather information on the enemies in the city before meeting with Shiroe, Naotsugu, Nyanta and Tetora. After the Mofur sisters arrive and are shown to still be at level 65, William joins the rest of the Adventurers present in sacrificing themselves to buy them enough time to bring Rieze and Shiroe's notes to Minori in Log Horizon's guild hall.

After they are defeated and sent back to the regular Akiba, William, Shiroe, Naotsugu, Nyanta and Tetora wait for the Akiba Guild Hall Raid Party at the Guild Hall. In the anime, William is seen giving Raid advice to Crescent Moon Alliance members after the city is restored to normal.

The Larks Take Flight Drama CD
William appears in the third track of the drama CD, in Silver Bow vs. Black Sword, which takes place right after the formation of the Round Table Alliance and before Silver Sword leaves for Susukino. Since he rejected his seat in the Alliance, William approaches Isaac to find out why the other Battle Guild guild master had decided to join. However, since they were both vying to be "#1 in the Yamato server," they end up having a duel.

Chain Chronicle
William was one of ten Log Horizon characters to be a recruitable character in the mobile game Chain Chronicle.

Log Horizon: New Adventure Land
William is a recruitable character in the mobile game Log Horizon: New Adventure Land.

Equipment
Despite running a Sniper build and typically staying in the backlines during raids, William has no trouble being in the front of a firefight once it comes to a duel. He has fought Isaac and Demiqas one-on-one, winning against the latter and coming to a draw with the former.

Trivia

 * In the first popularity poll, William came in 21st place out of approximately 40 characters.
 * In the second poll, he jumped 17 places into 4th place, in large part due to his tremendous popularity after The Gold of the Kunie.
 * In Season 1 Episode 9, William's stat screen is copy-pasted from Shiroe's; they have identical HP and MP values. Whether this is intentional or an oversight that wasn't caught is unknown.