The dwarves are building a new underground rail link between their city of Keldagrim and the cave goblins' Dorgesh-Kaan, but work is being held up by the discovery of ancient goblin artefacts, and they need the help of a qualified archaeologist. Helping them out should be simple enough - unless you stumble upon another H.A.M. plot against the city.
If Zanik is not following you, head back to the cave and talk to her.
Talk to the Goblin scribe in the house west of Ur-tag where you started the quest.
Speak to Oldak in the north-west corner of the city's lower level (there are stairs down in the house west of the scribe) to teleport to the Goblin Village.
Run south to the ladder, stay behind the houses on the west side to not get hit.
Climb up and kill the H.A.M. Mage and H.A.M. Archer, you must use magic or ranged. Throwing darts can work, only if you use the "long range" combat style. If you forgot a magic or ranged weapon, a crossbow and 50 bronze bolts spawns just to the west of your character upstairs.
Talk to General Wartface or General Bentnoze to receive ancient mace and two goblin warriors