The Spelljammer campaign setting for D&D beholder Tyrant Ship, but there are also monsters that reside in wildspace itself, just waiting to feast on unwary adventurers. There are even creatures so mighty that the vacuum of space itself does not harm them, and they are free to glide through the cosmos, waiting to devour spelljammer ships and their crews.
In many ways, the Spelljammer campaign setting is treated as a nautical-themed D&D campaign. The players must take care of their ship, as its destruction will leave them stranded in space. Luckily, the spelljammer ships are not defenseless, as many of them are swift, and come with powerful siege weapons that D&D players normally can't carry around, such as a mangonel. This means that players have a number of weapons at their disposal when facing the horrors that await them in widlspace, as they not only have their own class abilities and spells but the power of their own magical sailing ship to aid them in battle.
There are many conventional D&D monsters from the Monster Manual that can appear in wildspace, as D&D's Boo's Astral Menagerie (the Spelljammer monster book) has rules for adapting the old monsters to the setting. Boo's Astral Menegarie is also host to a number of powerful new monsters for DMs to unleash upon their party. Spelljammer might be the strangest D&D campaign setting to date and the designers of the Spelljammer: Adventures in Space went wild creating a suitably bizarre bestiary for the D&D multiverse.
The Neogi Are The True Enemy In D&D's Spelljammer Setting
Spelljammer is home to some of D&D's most frightening enemies, as both beholders and mind flayers have developed spelljammer ships and they use them to scour the cosmos for fresh victims. These creatures can be found in many D&D campaign worlds, yet the neogi call wildspace their home, as they travel in their insect-like ships, in search of plunder. The neogi are horrific spider-like aliens, who have an utterly alien mindset that is detached from that of most humanoid races. The most powerful among the neogi in the Boo's Astral Menagerie book, included with the D&D Spelljammer: Adventures In Space boxset, are the Neogi Void Hunters, who possess the ability to psionically enslave their enemies. These slaves are then used as crew aboard their spelljammers, or sent as cannon fodder into battle. The neogi are the ideal villains of a D&D Spelljammer campaign, as they are threats to the party without being overpowering (like the beholders and mind flayers), they have an established history with the setting, the neogi spelljammer ships and crews can provide an exciting challenging, and their alien mindset and desire for plunder means they can easily cross paths with an adventuring party.
The Eye Monger Is A Reverse D&D Beholder
One of the dangers that players can encounter in a Spelljammer campaign is asteroids and debris. It can be expensive to fix a spelljammer ship (unless the party had access to the mending cantrip), so groups will avoid any unnecessary damage by getting too close to space rocks. Unfortunately, it isn't always possible to avoid environmental hazards, as a party might need to hide in an asteroid field to avoid a more dangerous foe, or will need to search the shattered remains of an ancient monolith, in search of treasure. It's in these stretches of space that the Eye Monger lurks, as these creatures are indistinguishable from asteroids when they have their eye and mouth closed. As soon as prey draws near, the D&D Eye Monger 5e monster attempts to devour it whole.
The Eye Monger resembles the beholder race and the two share an odd connection. The central eye of the beholder projects a cone of antimagic, which can rob players of their magical protections and their ability to cast spells. The Eye Monger has an Antimagic Gullet feature, where any creature that is swallowed by its Bite attack will be shrouded in antimagic, which affects everything except artifacts and deity-level powers. Luckily, the victim can escape by dealing 25 points of damage to the Eye Monger from the inside, but they'll have to survive 10d6 acid damage at the start of each of their turns in the process.
The Lunar Dragon Is One Of The Most Powerful Monsters In Space
The dragons that are encountered in most D&D campaign settings worth one's time are territorial creatures, and those who stumble onto their lands may soon be facing a breath attack. Boo's Astral Menagerie features the Lunar Dragon, which are evil dragons that carve out entire regions of wildspace as their territory. They are called Lunar Dragons because they find desolate moons and turn them into their lair. These hollow moons are filled with the wreckages of ships that entered the Lunar Dragon's territory, with their lairs resembling a ship graveyard.
In of combat, all varieties of Lunar Dragon possess a Cold Breath, similar to that of the white dragons, as well as the ability to Phase, making it partially incorporoal and giving it resistance to the three physical damage types. These traits make the Lunar Dragon a potent threat for any D&D party, and their ability to survive in space means they can go toe-to-toe with spelljammer ships.
The Neh-Thalggu Is A Brain-Eating Psionic Spider Monster
One of the most horrifying things about the mind flayer is that they eat brains to survive and will often paralyze their victims using psionics so that they experience the pain of having their minds extracted up until the final moment. The Neh-thalggu is that concept taken up to eleven. These are creatures that once resided in the D&D Lovecraftian Far Realm alongside scary liches, but have made their way to wildspace in search of food. Neh-thalggu resembles massive pale spiders, with bulging red eyes. These creatures collect humanoid brains and each one provides them with a psionic spell. If the Neh-thalggu collects a brain, it gets the arms of Hadar spell, and each additional brain adds detect magic, magic missile, Tenser's floating disk, darkness, hold person, invisibility, spider climb, fear, hypnotic pattern, major image, and stinking cloud. Once it collects twelve brains, it uses its energy to return home to the Far Realm.The Neh-thalggu are essentially spider mind flayers and a Dungeons & Dragons party should run if they see one.
