|Spoiler Alert: This article or section contains details about plotlines not covered in the anime. Do not proceed unless you wish to be spoiled. |
A Crystal Bottle of Kales'Oh (カレス・オーの水晶瓶, Karesu Ō no Suishōbin?) is a multi-use item that can be used to store the proficiency of an equipped skill to open up a skill slot without losing progress in the removed skill. The bottle is a possible drop from a Forest Elven Hallowed Knight that can be encountered as part of the first chapter of the Elf War campaign quest on the 3rd Floor of Aincrad in Sword Art Online.
This bottle allows you to save the proficiency of any skill currently equipped in a skill slot.
Before the bottle is used, the user needs to use the properties window to select the skill they would like to store in the bottle. A skill already stored in the bottle can be retrieved by pulling out the stopper and inhaling the light-turned liquid inside the bottle. To store a skill already equipped, the user exhales their light-turned skill into the bottle, and the light turns into a liquid, the colour of which depends on the stored skill.
|Progressive Volume 3, Barcarolle of Froth, Part 2||Asuna used the bottle to retrieve her Tailoring skill previously stored in the bottle and to store the proficiency of her Sprint skill to open a slot for the Tailoring skill.|
|Progressive Volume 3, Barcarolle of Froth, Part 7||Asuna used the bottle to re-equip her Tailoring skill to craft a swimsuit for herself, a pair of black boxers with an orange bear patch as a Christmas present for Kirito, and later, a swimsuit for Kizmel.|