Shadow Dragons!

 Of the canonical D&D settings, Planescape is probably the one that I am most drawn to, conceptually. But it's in hard competition with Ravenloft. Both of these were introduced in the early days of the game, both (I think) formally introduced as full settings in 2nd Edition, in the late 80s and early 90s. Ravenloft was initially it's own kind of thing (actually, it might have been part of the Ethereal Plane,) but as of 5th Edition, it was made into a kind of demiplane or cluster of demiplanes that were in the Shadowfell.

The Shadowfell is actually quite new to D&D, only introduced officially in 4th Edition (there was a "Plane of Shadow" before then, to be fair). While the majority of Shadowfell stuff we've gotten in 5E, we don't tend to see a lot of the "greater Shadowfell," which is a more direct mirror of the Prime Material Plane.

And it's this plane that I think might be my favorite of them.

Yes, since a kid, when my favorite holiday was Halloween, I've always enjoyed a kind of spooky, gothic aesthetic (I did grow up in a creaky Victorian house,) and that kind of "Dark World" has always felt like a great place for adventures. What is heroism but being the light within a world of darkness, after all?

No monster is more synonymous with the fantasy genre than the Dragon, and it's right there in the name of the game, so it's fitting that there's a variant on dragons that has been touched by the Shadowfell.

My homebrew setting has a fairly well-fleshed-out Shadowfell and Feywild version, and the most memorable adventure of my original campaign was a journey across a region of the Shadowfell called Red Scar Plains. In it, the party needed to face off against a psychotic Fire Giant who ruled over the realm of Red Scar Plains (the region where the party was trapped). Their ally, a silver dragon named Sirkazan (or Sirk for short) had been captured by the giant, and was being kept there to allow shadow energy to gradually corrupt him (when they escaped, getting Sirk cured allowed me to come up with one of the coolest, grossest ideas I've had - they met a Nagpa who offered to cure Sirk if she were allowed to consume the shadow essence within him, which involved her cutting open his veins and pulling it out like strings of oil congealing into something like plastic, while the party fended off a band of rampaging orcs intent on attacking the Nagpa's lair).

Anyway, while Sirk avoided becoming a Shadow Dragon thanks to the party's rescue, the second-in-command of Red Scar Plains, and direct servant of the demigod emperor of the larger "Dire Kingdom" of which the Plains were just one territory, was an Adult Black Shadow Dragon named Kormod. The intent was never to let them actually fight Kormod, but they schemed with his daughter after killing off some of his younger wyrmling offspring to spring Sirk.

Shadow Dragons in 2014 were designed as a template - you would take a normal Chromatic or Metallic Dragon and change some of their features.

In 2025, Shadow Dragons now have two dedicated stat blocks.

The upside is that they're ready to use from the word go. The downside is that there's not any official guidance on homebrewing more powerful ones. The Juvenile Shadow Dragon stat block is Medium sized, and CR 4. That's on par with Red Dragon Wyrmlings, which are the toughest of the wrymlings.

The full-grown Shadow Dragon is either Large or Huge, but its hit dice are d12s, so it seems more "by default" Huge, and thus on par with Adult Dragons. At CR 13, it's actually on par with an Adult White Dragon, which is the least powerful of the Chromatic ones. Basically, if a Shadow Dragon is "Young," (Large-sized) it's more powerful than any other kind, but if it's an Adult (Huge-sized) it's near the bottom of the hierarchy - at least in terms of CR.

The truly terrifying thing about both Shadow Dragons is that their breath weapon will auto-kill a creature it reduces to 0 hit points - no death saves, just full-on dead and on top of that, spawns a Shadow to fight you.

Now, at the level when you're fighting a Shadow Dragon (level 9 probably at the earliest for a group of 4) a Shadow is going to be scary but not that scary, and easily killed very quickly. However, because you could potentially face off against a Juvenile as early as level 3 (a High difficulty encounter for 4 level 3 players would have a max of 1,200, and CR 4 is worth 1,100,) before you have access to things like Revivify, and when a Shadow is still quite a menace, these can be truly nasty encounters.

I'll admit I'd have liked to see a Dracolich and Shadow Dragon that rivals or even exceeds the most powerful of normal dragons, but admittedly, in both cases they're kind of curses.

A Shadow Dragon doesn't have the inherent magic that most adult-and-older dragons in the Monster Manual do. However, they are kind of the Rogues of dragons, able to hide as a bonus action while in dim light and darkness. Notably, a Shadow Dragon's lair (which only the adult version would get) actually reduces the effect of any magic that would shed bright light to dim light, so within their lair they should always have the opportunity to hide. Now, to be clear: the Shadow Stealth bonus action does not actually confer anything like cover or invisibility, so they will still need to do something like Disengage and get behind obscurement if they're not in total darkness. However, it does have Blindsense, so having magical darkness fill the Shadow Dragon's lair could be very helpful to them.

Generally speaking, I think the tactics with a Dragon are usually to stay at range, using the breath weapon when it recharges and then getting either out of range or behind cover. A Shadow Dragon is probably hiding on turns they can't use the breath weapon.

Now, how would we use one of these in a story?

If your campaigns are really locked to the Prime Material Plane, a Shadow Dragon could be in a place where there's some bleed from the Shadowfell, or, as the Monster Manual suggests, they could be in the Underdark (which tends to be, you know, dark thanks to the fact that it's underground).

Notably, this isn't a natural thing: Shadow Dragons are changed and corrupted by the shadow. So, a Shadow Dragon could have started off as a perfectly benevolent being.

Generally, when I think about the influence of the Shadowfell, I think it's a kind of deadening of emotions. The kind of ennui, depression, and the obsessiveness that comes more from feeling a compulsion to do something rather than genuine excitement about it. Dragons, of course, hoard things, but a Shadow Dragon might be consumed with a kind of hopeless, joyless type of hoarding, and perhaps what they actually hoard are the souls of the dead, trapped as Shadows like themselves.

In a sense, a Shadow Dragon is a pitiable creature, but no less dangerous for this fact.

While the Shadowfell isn't exclusively Ravenloft, and Ravenloft isn't exclusively Gothic Horror, I think you could play on those Gothic tropes, particularly Poe-style characters who behave in gruesome ways because of a kind of deadened sense of empathy - the two of his stories that stick the most with me are The Casque of Amontillado and The Tell-Tale Heart. In both stories, the narrator confesses to murdering someone on a kind of whim - in the former, there's an almost dismissive mention of a perceived insult, and in the latter, it's basically because the narrator is weirded out by his victim's blind, whitened eye.

A Shadow Dragon, I think, could represent a kind of faded majesty. While officially in the rules, only Metallic Dragons can polymorph themselves to look like humanoids, I 100% extend this ability to all dragons (at least those of adult age and older, though I think even a Wyrmling could do it if it fits the story). And I think a Shadow Dragon could present themselves as a regal lord, but one who has probably fallen into a brooding depression. Perhaps their lair - maybe a great castle - has fallen into ruin.

This character could present themselves initially as a friend, but turn more sinister over time. Admittedly, you could more or less use the same RP playbook as a classic vampire.

The other option is that the players hear about some great and powerful dragon, only to discover that their realm has fallen to darkness and despair. Now, the few remaining people living nearby speak of armies of shadows drifting across the land, and a greater shadow that blots out the moon with its wings.

A Juvenile Shadow Dragon could be a menace to a community that turns out to be more intelligent than initially believed. Signs of their activity could be hard to identify - a patch of grass in the woods that very suddenly rotted, or lurking shadow monsters growing in number of late.

Building an encounter with one of these, I'd very much design a map with lots of places to hide. It's always kind of difficult to build verticality into a battle map, especially if you don't have 3D stuff to use for it (I'd love to have Dimension 20's set-building team, but I do not believe I have the budget for it!), but flying monsters are always going to feel like more of a threat if they can, you know, fly.

In my mind, I'm imagining the ruined hall of some grand manor house - a massive staircase leading up to a landing on the second floor, with wide hallways leading off on both the first and second floors. The Shadow Dragon could then use the floor of the second floor/ceiling of the first floor as a way to hide and forcing mostly ground-bound characters to have to chase them.

Now, death from their Shadow Breath does automatically happen if you reduce a character to 0 HP, even if it's a successful save. At the levels where you're fighting the adult version, I'd hope you have at least one character that can Revivify (at level 9, even half-casters can,) but throwing a Juvenile one of these at a tier 1 party is going to be rough. Make sure that your players are bought-in for truly deadly monsters, and if not, make sure that there's some way for them to resurrect characters such as friendly NPCs or remote holy shrines or the like.