Undaunted has a fantastic mix of card play (deck building) and board play that creates a unique experience. Reinforcements adds the ability to play solo as well as new units and scenarios.
For me, the game is a solo only experience and having campaigns to play through (when combined with Normandy) with different setups and win conditions makes for a very satisfying experience. You also get to play through both sides so there is A LOT of gameplay here. The games don't last too long but are long enough to see your deck building pay off.
The solo play is a bit more than an automa deck, with individual charts for each unit. It seems daunting at first but it was surprising how quickly it became a smooth experience.
Overall, Undaunted as a whole is a fantastic experience with its unique combination of board play and deck building. The addition of reinforcements opens up solo play as well as new units making for a top tier game that is a hybrid of puzzle and dudes on a map combat.