The Woldcore Caves

From the introduction: Long ago the dwarves accidentally tunnelled into goblin-mines while searching for precious metals, and now they are locked in perpetual warfare – both are well defended and neither can gain the upper hand. The players join the dwarves and must learn to understand underground warfare, travelling through hundreds of miles of treacherous caverns. Each side has bases and scouts around the outside. They attack by attempting to get past a scout group without the other side managing to get a warning signal back, then attack the enemy unprepared in their homes.