Moonberry

The moonberry is a magically-created berry that appears in the EMPATH: The Luckiest Smurf story "The New Shop In The Village". It has a glowing power from inside the berry, and its purpose is to give whoever eats one a sense of euphoria, although eating too many of them can cause adverse effects such as putting them into a near-death state that can become fatal.

The berries were discovered by Trenchcoat Smurf, who found a bush full of them by the waterfalls in the Smurf Forest. Upon gathering a bunch of them, he offered them to Chatty and Nosey as a temporary substitute to smurfnip that they could serve to their customers at The Wake N Bake Brew Shop. The unintended effect of the Smurfs eating that many berries is that they started to eat the roof off the Wake N Bake, under the assumption that the mushrooms used to construct Smurf houses have magical properties in them that would allow them to see visions.

As it was eventually revealed, Beguiler is the one who created the moonberries, using the reconstructed Orb of Euphoria to create them. With the destruction of the orb, the moonberries were also presumably destroyed, and the Smurfs who were affected by the mass ingestion of moonberries were restored to full health.