A vast network of underground tunnels, the Underdark is a place rife with some of the most terrifying monsters in Dungeons and Dragons.
Perhaps the most recognizable monster in Dungeons and Dragons, you, if not your character, have probably beheld a Beholder. Cunning and intelligent, Beholders are inherently powerfully magical creatures who will try to end a battle as quickly as they can whenever possible. With their many eyes looking in every direction at once, it’s nearly impossible to ambush or surprise them, and when they do see you they will likely attack viciously. Beholders don’t like anything not like themselves and are often greedy, wanting both power and wealth alike.
These creatures were once mind flayer tadpoles who had undergone neoteny. If a tadpole tank was left unsupervised for a length of time for any reason – for example the destruction of that mind illithid community – the tadpoles would begin to eat each other until the last survivor was gargantuan monster that even the mind flayers despise. They search out intelligent life so they can eat their brains, but Neothelids themselves have such a low intelligence that even the Elder Brains can’t detect them. However they do have psychic abilities, able to levitate, resist magic abilities, and sense sentient beings as well as using telekinesis to move things around.
An adventurer who isn’t paying attention in the dark may mistake the Roper for a rock formation. They generally stay very still and wait for a potential victim to happen by, looking very similar to the surrounding stalagmites, and when someone gets too close they quickly lash out with their tendrils and wrap around their unexpecting prey. Despite looking like rocks and moving only slightly more frequently, Ropers are generally intelligent creatures, learning about their surroundings and contemplating philosophy for long periods of time between meals.
Once upon a time the Raven Queen cursed thirteen wizards for preventing a ritual that would have helped avert a war between the gods, and the resulting creature is the bird like monster known a the Nagpa. Thanks to their cunning and willpower all thirteen somehow remain alive to this day, but they try their best to avoid the Raven Queen and all that serve her. Nagpa mainly stick to the shadows, manipulating events as best they can with the intention of bring ruin to the remaining world and then looting the treasures and knowledge of these collapsed civilizations.
As tall as a house and looking like they’re made of shadow itself, Nightwalkers are sentient undead monsters from the Plane of Shadow. They take pleasure in the suffering of others and have power over darkness, making them one of the more malicious and scary things to encounter in the dark. Once defeated, a Nightwalker can turn a human into an undead creature devoid of a personality or soul known as a Bodak using an ancient ritual of warped void energy.
Has your adventuring party visited the Underdark? Which monster lurking down there is your favorite? Which would you most rather fight? Let us know in the comments!