Zork Zero

The Great Underground Empire is in its heyday. Upscale condos crowd the massive caverns. Subterranean highways stretch from Aragain to the Fublio Valley. And no adventurer has yet set foot in the open field west of the white house. But now both town and countryside are being abandoned, their inhabitants fleeing in the wake of a dread wizard's curse. The curse has already disposed of the royal Flathead family. It threatens to destroy the whole kingdom - unless you can stop it. (ifdb.tads.org