If You go to the deepest spot of the map were there is purpul crystals and Water as far down as You can You Will se like yellow holes big holes in the Stone Walls and don't bring glide suit and climb pick You Will die trust me.
Tame an megalosaurus whit 130 level or higher and just pump meele and health and it Will make the rock drakes and the animals down there look like cats don't forget to get 1 extra radiation armor set and an fully Charged bulldog whit 600-1000 chargé of light Good Luck and the rock drakes babies eat Nameless venom just use the mega to kill them GL
They lose 1 point of food every 15 seconds, so to time how long until they start starving, multiply their current amount of food by 15 and then divide by 60 twice. This will give you the number of hours left untill the food stat reaches 0.
((15 x food)÷60)÷60
Obtaining this creature will require you to enter the tek trench where puprle liquid and the nests of these creatures lay past the bioluminescent chamber, there you must steal an egg and raise in a cold environment feeding it nameless venom you can get by killing nameless