From Spielbox Magazine 2011 Issue #3.

It was later available in a pack of promos for backing Game Boy Geek 2017 Kickstarter campaign

Stevie Wonder is an additional leader for 7 Wonders: Leaders expansion, and is only playable with that expansion.

With his help, you can build a stage of your Wonder of the World; instead of paying the required number of resources, you pay 1 coin for each resource that the stage would cost and slide Stevie under the appropriate stage face up. Stevie does not interact with Imhotep (another leader that reduces the cost of your Wonder stages by 1 resource each).