Tunneling A character may tunnel through substances by making a Body Test versus the target number on the chart below. Apply a +2 TN Modifier if the character's tools are inadequate. The amount they can excavate per hour is equal to the amount on the chart below times the number of successes on the Test. A Civil Engineering Test can be used as a Complimentary Skill Roll. For deep tunnels, the character must make a Civil Engineering Test against the same target number per day to avoid a collapse. At the end of the tunneling project, the character must make an Open Civil Engineering Test. The result is the Barrier Rating of the tunnel's walls, indicating the structural integrity of the walls versus magic or explosions. If the walls are breached, the tunnel collapses. Tunneling Material Target Number Amount (in m2) Soft Soil 4 (4 x Strength) Compacted Soil 5 (2 x Strength) Loose Rock 6 Strength Soft Stone (Limestone) 8 (Strength/2) Hard Stone (Granite) 10 (Strength/4)