Endeavour


 * "The Best is not always the most Obvious." - The Last Will and Testament of Grimbeard the Ghastly

Endeavour is the sword of Hiccup Horrendous Haddock III, which he acquired in How to Be a Pirate and uses in every book thereafter.

History
Endeavour originally belonged to Grimbeard the Ghastly, and was his favorite sword. It was left in the sea cave with the rest of his treasure. When Hiccup, Fishlegs, and Alvin the Treacherous wound up in the cave and Alvin attacked Hiccup, Toothless grabbed the nearest available sword and tossed it to Hiccup. The sword looked unimpressive, but allowed Hiccup to discover that he was actually a talented sword-fighter when using his left hand, and hold off Alvin.

After escaping from the cave, Hiccup brought the sword with him. After a dream in which Grimbeard spoke to him, Hiccup looked closer at the sword's pommel and found a hollow where Grimbeard's true will was concealed. The will revealed the sword's true identity, and thus Hiccup fulfilled the prophecy that only Grimbeard's "true heir" would find his treasure, and his legendary sword (this was originally thought to be either Snotface Snotlout, who found a much smaller treasure chest from Grimbeard's hoard, or Alvin, who had found the flashier Stormblade that also once belonged to Grimbeard).

Hiccup uses Endeavour in all the subsequent books, and it has allowed him to successfully defend himself from Alvin, Norbert the Nutjob, and even the Hairy Scary Librarian. Hiccup always keeps it with him in case he is attacked by Driller-Dragons.

Like Hiccup himself, the sword is small and unimpressive at first sight, but very reliable in a tough situation.

Film Adaptation

 * In the film adaptation, Hiccup does not use any weapons to any appreciable degree. In Dragon Training, he initially carries a battle axe given to him by his father, Stoick the Vast, but it is destroyed a few days into training.