The base game is a good game, but its simplicity makes it too predictable. Its strength lies in that you can get a group of new players playing in a minute or two, but it lacks replayability once you have seen it play a few times. This expansion makes it a much more complex game. Enough that I would introduce new players to the base game first. For an experienced player, the complexity really pays off. When someone retires a hero and gets 3 victory points ahead, you know you have to retire your hero too. This starts a delicious arms race to cycle through heroes which forces adaptation as well laid plans fall apart in the face of hero powers and the drive to fulfil hero needs.