In the post-7DRL cooldown, I've been putting some touches on the Ardennes game that I had hoped to get into the game during the competition but didn't have the time to complete.
The main new feature is a new mission, called Cat and Mouse. You are trying to evacuate a field hospital when a sniper opens fire. You have to flush out the Master Sniper from the surrounding village before the Nazi front arrives so you can get the wounded soldiers in the hospital to safety. It features a fun hidden enemy mechanic with custom Focus cards for sniffing him out.
Another new feature is the new Wound Cards. Instead of just applying a condition, wounds now get inserted into your focus queue, polluting your ability to respond to challenges if you don't keep on top of them.
Finally, there's a new method for responding to attacks my enemy forces - a new Flip Defense system. When an enemy attacks, you will (usually) get a chance to flip a card out of your queue to prevent its effect. Just make sure you have the right cards available or else you'll suffer fire! Hexes with particularly good stealth or tactical advantage give you additional "flips", but they must be shared by all soldiers in that hex, so be careful!
Enjoy the game.