The final battle game consists of two rounds, during which each of the 2 groups reveals their decks.
In each round there are 20 points at stake - 2 points for each card played and unplayed.
The group presenting their cards gets 2 points for each card revealed minus the last card played if the era is guessed.
The guessing group gets 2 points for NOT revealed cards + the last card played.
Thus, if a group guesses the epoch from three cards, they get 16 points: the number of unrevealed cards + the last card played is 8. The other group in this case gets 4 points: the number of revealed cards minus the last card - 2.
If the epoch remains undiscovered, the group that revealed its pack gets all 20 points.