Warhammer Underworlds:...
As the battles under the Gnarlwood intensify, warbands struggle to establish control over even the smallest areas of the rootmaze. A canny strategist knows that the answer lies in doughty fortifications - so their warriors rig unclaimed territory with traps and build up walls into an unbreachable bastion, even as the enemy approaches. The most successful combat engineers may even claim the title of Castellan of the Fearsome Fortress!