The campaign gives Twitter users the chance to send potions and cast spells on the people following them. The three options on offer include shrouding the follower's Twitter page in darkness, sending a flock of birds that fly across the screen and declaring affection for a follower by sending a love potion.
A website hosting the campaign has been set up to back the launch of Harry Potter and the Half-Blood Prince, which debuted in UK cinemas last week.
It also enables Twitter users to choose from a range of messages to send to followers such as, 'I made you this love potion because I no longer want to hide my feelings for you under an invisibility cloak.'
The campaign was created by Warner Bros and aims to drum up interest in the launch of the latest film in the Harry Potter franchise.