The Blackwyrm Coat (ブラックウィルム・コート, Burakku Uirumu Kōto?) is a player-made black leather coat, tailored from black dragon leather, a high grade raw material, by Aincrad's best player seamstress, Ashley, that Kirito wore in the final months of Sword Art Online.
- The Blackwyrm Coat was Kirito's fourth leather coat in the game.
- Kirito tended to wear this coat even in the middle of summer, saying that he had become so used to it that he could not calm down without having it on.
- The Blackwyrm Coat was among the items that Kirito inherited in ALfheim Online from his Sword Art Online save data, due to the two games having an identical save format. However, as all the items were corrupt and could have been detected by the system's error detection protocol, Kirito deleted all of the items.
- Light novel illustrations depict Kirito wearing a coat identical to Blackwyrm, as early as February 2024. If it is the same coat, then this means that the Blackwyrm Coat was in use for the better part of a year, meaning his other 3 coats were used for a relatively short amount of time. However, it is also likely that Ashley tailored multiple coats that look alike, for Kirito.
- The metal piece of the baldric worn on the coat is actually a breastplate, named «The heart of the relic» (ハート・オブ・レリック, Hāto Obu Rerikku?). According to lore provided to the anime staff by the author, it was once the core of an ancient machine.