As some other commenters have stated, there is no win condition printed in the text, so as a solution you can just follow what the other games in this series have done: If you get a red joker and the two cards are face cards, you found a portal to your old fortress above ground and you can resume your evil plans. As a symbol of power, the fortress reduces the mutiny threshold of all units by 4, and the treasures you had in your fortress are worth 500 trade goods if you decide to keep playing. For tryhards, if you reach floor 30, you break out onto the surface. Now with the ability to tunnel anywhere and invade the heart of any surface city at the drop of a hat, you quickly take over the world.