The Arachnid Nest is home to Regalis, Goddess of Poison; also known as the Spider Queen. As you can see, the Arachnid Nest is the darkest environment in the game and has a unique aesthetic that sets it apart from everywhere else.
In this environment, your primary task will be to collect spider eggs for Regalis. Some spider eggs are under attack by greedy poachers and you’ll need to fend them off before collecting them, while other eggs hatch hostile Arachnalisk creatures (a new race!) that need to be slain. Some spiders might become extremely attached to you and will help you fight until you return them to Regalis’ altar.
Note that this screenshot is just a mockup to show you some of the objects found in this environment. Not all of the objects are pictured below, and many of them are animated in-game.