The Mayhew Tunnel is a level of the Mayhew sewers which is connected to the Goblin Head Tunnel. It is only accessible after completing one of the goblin or ratman quest lines in the Sewer Tunnels, which culminates in The Siege of the Ratman Fortress or The Siege of the Goblin Fortification, respectively. The one alternative is to simply destroy the goblin fortification without completing any of these quests. In the Mayhew Tunnel a hero may search for a way out to the Mayhew city proper with the Finding Mayhew quest. This finishes the alternative of The Trial of Venn's Spire quest to allow a hero the ability to leave Valmorgen.
In-Game Description: This area of tunnels seems to have been dug through rock and dirt. A faint drumming sound can be heard now and again.
- Slight Fortification: Goblin Watchtower, 3-5 Goblins, 5-6 Goblin Archers, 3-4 Goblin Priests and 1-3 Goblin Champions. Rewards various items including: Level 2 Weapons, Junk
- Ratman Raiding Party: 2-4 Ratmen, 1-2 Ratman Champions and 1-3 Ratman Shamans. Rewards various items including: Level 2 Weapons, Junk
- Ratmen lair, filled with Goblins: 7 Goblins, 5 Goblin Archers, 2 Goblin Priests and 3 Goblin Champions. Only available if Hero has the Finding Mayhew quest.
- Escaped Merchants: Only available after freeing them from the Ratmen lair, filled with Goblins.