XKCD is a webcomic created by Randall Munroe. The comic's tagline describes it as "A webcomic of romance, sarcasm, math, and language".
To download this Add-On, we highly recommend you do it via the user interface in Kodi. Simply look for the "Get More" button in the Add-Ons menu. If you want to install it manually, you can direct download the zip below then in Kodi, look for the "Install via Zip" option.