Pottermore is set to post a surprise each day between the 12th and the 23rd December, including new writing from J K Rowling.
In a newsletter sent to Harry Potter fans, Pottermore said Rowling will write about Draco Malfoy, a pupil at Hogwarts and one of Harry Potter’s nemeses, as well as Florean Fortescue, the owner of the Ice Cream Parlour in Diagon Alley.
Other daily treats, which will be released at 1pm every day, will include gold Galleons and new portions to use on the site.
To unlock the treats, users will have to solve rhyming riddles. They are also encouraged to follow the development on the Facebook page, using the hashtag #PottermoreChristmas.
J K Rowling has contributed several articles to Pottermore this year, including a biography of her favourite “off-stage” character from the Harry Potter series – singer Celestina Warbeck.
In July, she wrote a piece about a 30-something Harry Potter and his friends at the final of the Quidditch World Cup 2014 for Pottermore, told from the perspective of infamous gossip columnist Rita Skeeter.