"Neither steel nor stone could cause any damage, my Lord... It was simply too big, unlike any enemy we have ever seen."
Legion Captain Meron's last report to General Lorgar
"When the trees shuddered and the earth shook, we knew it was far too late to retreat."
Excerpt of General Lorgar's last report to Emperor Paulus, following the loss of his entire army of 10,000 men
Darklings are a kind of Halflings living in the sewer of medium to large cities.
Even though they smell badly and are quite dirty, Darklings are friendly and clever.
They try to limit the knowledge about their existence to only a small number of trustworthy persons, including player characters.
Darklings trade in information. Money, weapons and magical items have no value for them. This is why they hide beneath the sewer grates, listening to all that is said in the city above.