What is the ERC (European Research Council)? Find more information here:

-ERC website
-Euresearch: the Swiss guide to European research & innovation

Q: Are smaller projects allowed in the Synergy Call?

The projects enable a minimum of 2 and a maximum of 4 PIs and their teams to collaborate. The size of the projects depends on the content. If you come up with an idea that needs 4 PIs and only 1 million, this is perfectly fine. There is no need to ask for 10 M and to pack it with zillions of ideas to have a broad and not clearly defined scope.