Sound Analysis

This proficiency allows a character to gauge the size of underground areas by generating noise and analyzing the echoes that return. Using this skill, he can calculate distances up to one mile, and determine sound direction.

To use sound analysis, the character must work in absolute silence. The sound created must have a sharp, staccato quality. A howl or wail is ineffective, but a clicking sound, or loud "hey" works well.

The PC must make a proficiency check. If the check is successful, he has correctly analyzed the size of the area in question to within plus or minus 25% of its height, width, and length. If the check fails, the echo has become garbled in its reverberations. No further attempts by the PC to analyze that area will succeed, though others with the proficiency may try.

A proficiency check of 5 or less means the character has learned not only the size of the analyzed area, but other details as well: the number of branching side passages, whether there is a straight or wandering corridor, and whether or not water exists.

The disadvantage of this ability is that, while it is useful for learning about a completely unknown area, it announces the characters to all creatures in hearing range. They will certainly be prepared, and may go looking for the intruders.

[Complete Book of Dwarves]