Ankheg The ankheg ( ÆNK - eg ) was a huge insectoid monster with many slender limbs and large antennae . It burrowed underground and hunted from below . Environment . Living in warm climates , the ankheg dwelt in partially collapsed burrows usually around 40 feet underground . The ankheg hunted in forests or grasslands where prey would wander into its traps . If an area became too barren , the ankheg moved on to other , more lucrative areas . Ankheg tunnels were sometimes filled with the remains of victims , eggs , or chitin . Their tunnels would sometimes be around 60 to 150 feet long and 5 feet high . Hollow tunnel ends were used for lair purposes , such as sleeping or hibernation . Combat . The ankheg was an ambush predator that waited around 5 – 10 feet underground for prey to wander into position . The attack was quick , as the prey was crushed and ground in its mandibles and assaulted with acidic digestive enzymes . If a foe proved too difficult , the ankheg could also squirt acid to take it down . If several ankhegs were attacking a group , the ankhegs would try to attack different targets . If prey was attacked by more then one ankheg , the ankhegs would just play tug - of - war with the unfortunate prey . Ecology . A typical area could have a lone ankheg , a pair , or a cluster of ankhegs . Diet . Gaining nutrients from the ground , the ankheg also had to hunt fresh meat to sustain itself . It could also eat decaying meat . Physiology . Ankhegs had darkvision and tremorsense for 60 feet , and strong chitin armor . The " attack " acid was part of the digestive system for the creature , so it couldn ' t digest food for six hours after after a discharge . Ankhegs that lived in colder areas hibernated during winter . During this time , an ankheg took nutrients through its shell and its antenna . Life cycle . Ankhegs mated in autumn , when the fertilized female would kill the male to lay 6 – 12 eggs inside him . Usually , a high number of eggs survived and hatched within two to ten days and started to feed . An ankheg broodling did not hunt and remained hidden , while its mother brought it sustenance . After a year , the young were able to fend for themselves . Around the second year , the young ankheg shed its chitin before winter . It took a little less than ten days to complete the process and grow a new shell . During this time , the youngling was slower and more vulnerable . To defend itself , it secreted a fluid that smelled like rotten fruit . This defense could backfire , as some would seek out the smell . Usage . Ankhegs could prove to be useful for a farmer . Provided it stayed alive , its tunnels could bring in water and its excrement contained enriching minerals . An ankheg shell harvested from a slain ankheg weighed 100 lbs . Armorers like Taerom Fuiruim in Beregost could forges armor from the shells . It took three days to make . The armor was very nearly as effective as full plate mail , but weighed considerably less and could be worn by warriors who usually couldn ' t wear such heavy armor . Taerom claimed to sell ankheg armor to rich nobles for 20 , 000 gp . However , if one provided the shell , he would charge just 4000 gp for a set of completed armor .