The campaign, created by Carat and Swapit, encourages 6-11-year-old boys to find 16 different Mini Figures which have been hidden within ads on websites such as Nickelodeon, Cartoon Network and Toonattick.
Once a child has found and clicked on the ad, a Mini Figures Lego character will appear on-screen.
For every character found, a child will earn 20 Swapit points. Once all characters have been collected, they can enter a prize draw to win real Mini Figures.
The eight-week campaign will be promoted to kids via banners, emails, news and messages, which link through to the Mini Figures campaign site. This will also provide clues as to where certain characters can be found.