Given That Nadarresh's Nature and Dungeoneering are equal, his result for the do I know anything about the Tentacle this should have revealed the following:

This disgusting aberration is known as the lurker below.  The lurker below dwells in deep chasms and forgotten places scavenging almost anything for food. They have powerful tentacles to grasp prey and a huge maw. Their bite is filled with the filth fever disease; they have an unnatural cunning and are sometimes found in dark tunnels beneath ancient cities and ruins.