Eternal mimics the intimate 1v1 format popularized in other CCGs (collectible card games) like Hearthstone and Magic: The Gathering.
Much like in other CCGs, Eternal players collect cards and use them to construct custom decks which they then use to try and best other players decks. The cards players collect are spread across a number of different color variants, card types, and keywords, allowing for deck strategies which range from simple and straightforward to mind-bendingly complex, and every shade of gray in-between.
Source: N4G PC Looking for a Hearthstone alternative? Give Eternal a shot