There's no better time to be had by 2 in a dungeon
The premise is simple and great, you've got a team of 8 in a secret dungeon, which is presented little by little and that is constantly changing. However, in your starting line there're only 4 guys, hiding the rest of your team and equipment within the secret rooms of the dungeon.
Some have compared it to chess or an abstract game, that wouldn't be too far off as to describing how you move in it. However, I think there's still so much more with the different configurations of teams/equipment you can come up with and the unpredictability of the layout of the board, which makes you stay alert during the whole game.
It's also great that you start with the same figures and equipment, it's got a simple but effective combat system (like the one used in LOTR: The Confrontation), and different options for scoring points means that this is a game with many different endings.
In the end, I feel this is a light-medium game, with lots of strategical options and a lot of flavor in it, to make it to the top of my list.
DT is a great 2-player game out of France, with no shortage of expansions. A game I really like this game as it's fun, short, challenging and engaging.