Abstract: One or more videos are presented to a user. The videos include a plurality of hidden artifacts. The videos also include advertisements. The user looks for the hidden artifacts in the videos. Whenever the user finds the hidden artifacts in one of the videos, the user selects locations in the videos that correspond to the hidden artifacts. A computing device performs different actions depending on which ones of the hidden artifacts the user is able to find. For example, the computing device can provide different rewards to the user depending on which ones of the hidden artifacts the user is able to find.