Portal Games created an 2018 event kit with promo-cards for each faction of the base game. If you participate in the event, you can keep the 3 promo-cards of the faction you've played with at the event. For each faction you get 3 copies of the same card.
The Barbarians get a card called 'Raid' and has a feature: each time you raze, get 1 star.
These cards are alternate artwork cards and replace the Raid cards found in Barbarian's deck in the base game
Imperial Settlers: In-store Event Kit 2018