The real kobold tunnels are small and can only be crawled through.

However they also purposefully have medium tunnels through which you must crouch, these tunnels are for the bigger folks and parts of their traps, as they have made sure to leave stones and pitons on the roof at the height that an careless explorer would gash their head if not wearing a helmet.

Kobolds also known as Knockers look like the cross between short haired dogs and rats, they smell of the musk of wet animal fur.

They are treacherous, and know they are small and weak, so they rely on other methods and tactics than frontal confrontation with larger threats.

Knockers delight in the stink of fear and despair of others. So they will lure in targets and inflict extended despair on them by capturing them in traps or nets so they can collect the aromas.

Caves inhabited by knockers are permeated with the smell of fear from their many targets. Causing those entering their lairs to instinctively sense dread.