Thursday 9 November 2023

Dragons Reviewed and Ranked

The AD&D 2nd Edition Monstrous Manual lists 23 types of dragon. I here intend to review and rank them as they are presented in the text (i.e. not as reimagined by a creative OSR-influenced DM). Each dragon type is assigned a score out of 5 across three metrics: evocativeness, usability, and coherence (the latter being a shorthand for a pleasing congruence between abilities - breath weapon, magical abilities, and so on). The scores are then averaged and the dragons ranked. 

Without further ado, let's begin:

Black Dragon

Evocativeness: 3. 'Black dragon' conjures in my mind a reference to Ancalagon the Black, the original dragon in Tolkien's Middle Earth, but the D&D version is a lot more humdrum. There is also a major redundancy problem given the existence of the green dragon - which can already be said to have the marsh/forest/jungle/noxious miasma angle covered. With that said, a swamp or marsh is a kind of overground equivalent to a mythic underworld, and I like the idea of there being a dragon lurking at the heart of each. 

Usability: 3. It is hinted that black dragons' lairs are supposed to be at least partially flooded, or accesible through waterways. This adds an interesting dimension - but, sadly, is not really followed through in the text.

Coherence: 2. There is a conceptional confusion at work here. Black dragons' abilities suggest a dweller in dank, dark, damp places - darkness, corrupt water, summon insects, charm reptiles. But why is the breath weapon acid? This has never made a great deal of sense to me.

Overall: 2.666

Blue Dragon

Evocativeness: 4. It's possible that the creators of D&D were the first to dream up the existence of blue dragons, at least in published material. (Somebody will inevitably pop up in the comments to inform me that actually they first appeared in a Edgar Rice Burroughs novel from 1907, but whatever.) Why would a desert-dwelling dragon be blue, and breathe lightning? I don't know, but it feels very redolent of D&D during the TSR era.

Usability: 3. I am in favour of deserts as settings for campaigns, and it is important therefore that there should be lots of desert-based monsters. A desert-based race of dragons therefore comes in handy.

Coherence: 2. To repeat: why would a desert-dwelling dragon be blue, and breathe lightning? And how is that consonant with its magical abilities, which are mostly to do with creating hallucinations? There is too much going on here: blues are a 'busy' type of dragon, and it dilutes their impact.

Overall: 3

Green Dragon

Evocativeness: 4. Dragons are classically green, and I like the fact that green dragons exude poison, and indeed poison the landscape around them. This is Saint George! This is Glaurung! This is the Lambton Wyrm! This is more like it.

Usability: 3. Here, however, the overlap of functions and purview between green and black dragons again becomes problematic. Green dragons are 'about' poison, and this suggests swamps, bogs, and the like. But that's a black dragon's territory. If on the other hand one conceives of them as a kind of 'forest' dragon, this would not be suggestive of having abilities associated with poison. This in practice makes it difficult to imagine where exactly green dragons 'fit', if they are not to step on the toes of the blacks.

Coherence: 3. See above. Yes, it makes sense for green dragons to be associated with poison. Yes, it makes sense for them to have the magical abilities they have - warping wood, entangling, growing plants, and so on, if they are supposed to be a 'forest' dragon. But one of these things is not like the other.

Overall: 3

Red Dragon

Evocativeness: 5. Nothing says D&D more, really, than a red dragon - and to somebody of my age, the image of a red dragon and its treasure is almost synonymous with the experience of playing D&D (the very first session of D&D I ever played in even featured one, I suspect because one appeared on the cover of the Red Box and was therefore present in our minds from the very outset). It therefore communicates a mood, and a sense of nostalgia, that is almost quintessentially of the TSR era which we remember so affectionately.

Usability: 4. Covetous and greedy, sits on a big treasure hoard. We get this. Everybody gets it. And it is beautifully uncomplicated and pure. The game is Dungeons & Dragons. At the bottom of the dungeon is a dragon. It is red. It breathes fire. This works, and we all instantly recognise that it does so. The text also includes a nice little titbit: red dragons like to eat young maidens and sometimes charm local villagers into sending them as sacrifices. It writes itself.

Coherence: 5. It is hard to really imagine what image the word 'dragon' would conjure in people's minds were it not for the cultural impact of Tolkien and, in turn, D&D. The red dragon, which can breathe and manipulate fire, find treasure, and use powers of suggestion and hypnosis on its prey, is so redolent of Smaug and Glaurung that it taps more or less directly into that shared imaginary history, and is thus really the most coherent dragon type of them all.

Overall: 4.666

White Dragon

Evocativeness: 2. The idea of white dragons is sound. But it is by-the-numbers. While the blue dragon has a pleasing oddness to it (it lives in the desert and therefore it is blue and breathes lightning), the white dragon is lazily obvious. It lives in cold places and it is white and does cold things. OK.

Usability: 4. The virtue of white dragons, however, can be said to lie precisely in their banality. As is the case with desert campaigns, I am fully behind the 'ice world' motif - and monsters suitable for use in icy places are thin on the ground in D&D. White dragons, in this respect, need our support.

Coherence: 4. White dragons breathe cones of frost, and have spell-like abilities that chiefly revolve around manipulating cold weather, wind and fog. This all makes perfect sense, although it does raise the question as to whether it is really plausible that a monster that makes its living in very cold places would mostly seek to kill or subdue its enemies by deploying the cold itself, to which they are presumably immune. 

Overall: 3.333

Amethyst Dragon

Evocativeness: 2. Amethysts themselves suggest regality, and it is therefore appropriate for amethyst dragons to be described as wise and aloof, and vaguely snooty. But does this not describe the stereotypical image of all dragons? Delusions of grandeur, arrogance, and a strong sense of entitlement? It is hard to discern within this a USP (a problem that also bleeds into amethyst dragons' coherence, too). I think what the designers were going for was a neutral equivalent of the (evil) red and (good) gold dragons, the correspondingly most powerful representatives of their alignment groupings. Fine: but this in itself does not add up to a distinctive character. 

Usability: 2. Partly for the above reasons, amethyst dragons greatly overlap conceptually with red dragons and, as we shall see, gold dragons and others, too. It is a powerful, wise and conceited being that dwells deep in subterranean caves and likes treasure. Yes, but we have those already. What, aside from psionics, do amethyst dragons bring - metaphorically and literally - to the table?

Coherence: 2. Amethyst dragons' abilities and breath weapon also reflect a lack of a strong sense among the designers about what they were designing. An explosive concussion-lozenge breath weapon conjures an image of a dragon spitting out cough sweets, but alongside this they are able to walk on water, neutralise poison, shape change, control weather and cast resilient spheres - a smorgasbord of abilities that suggest not so much 'paragon of True Neutral' as 'mishmash'.

Overall: 2

Crystal Dragon

Evocativeness: 1. I have never been a fan of 'friendly' monsters, having I think been scarred by too many experiences with 'friendly' GMPCs in the days of my youth; the word makes me immediately smell a rat. And I think 'friendliness' is especially to be avoided when it comes to dragons. It is undignified. 

Usability: 2. A dragon type which is friendly and curious, prefers conversation to fighting, and is 'fun loving and mischievous' suggests to me one thing only - a self-conscious 'good guy' with some sort of role in an overarching plot. D&D should not be about unrelenting hostility, but there is a problem when the only possible encounter that can be envisaged between the PCs and a particular monster is benign; in such circumstances we immediately begin to descend the slippery slope into railroading. 

Coherence: 3. The crystal dragon has a nice breath weapon - a cloud of glittering shards that dazzle as well as wound. And its abilities are consonant with the role that the monster is evidently supposed to play in the minds of the designers, having a mixture of mood-altering and gift-giving spells at its disposal. I'm not a fan of that role, but the suite of abilities makes sense in its own terms.

Overall: 2

Emerald Dragon

Evocativeness: 4. A dragon which lairs only in 'tropical and subtropical extinct volcanoes' is working a narrow niche indeed, but I rather like that niche: it conjures images in the mind of 'lost worlds' in far flung places, like Venezuela, Belize, Myanmar, Indonesia, the Philippines, Fiji.... 

Usability: 3. With the above said, emerald dragons suffer from the same kind of identity crisis as does the amethyst. What is really all that different in the end about a dragon which is described as paranoid, possessive, and vengeful? However, the idea of a dragon which prefers to hide, set up traps, and attack with burrowing ambushes than direct confrontation is I suppose at least somewhat more distinctive than many of the other types. 

Coherence: 2. Emerald dragons breathe sonic vibrations. Why? Not sure, except that it probably felt to the designers like one sort of dragon ought to have that type of attack, and the emerald might as well be it. Its spell-like abilities are a grab-bag: some stuff to do with confusion, a bit of hypnosis, a bit of hold person, some rock manipulation, and geas. 

Overall: 3

Sapphire Dragon

Evocativeness: 1. What is there to say? Sapphire dragons, we are told, are 'militantly territorial' but not actively hostile, and their reaction to intruders basically depends on how those intruders comport themselves. Inspiration was clearly running dry here; this is the dragon equivalent of a bowl of cornflakes without sugar. 

Usability: 1. Lacking distinctiveness, sapphire dragons have little to recommend them to a DM stocking a hex map or dungeon, when so many other dragon types will do. Indeed, the text even says, more or less openly, that there is a big overlap between sapphires and emeralds, with the implication that one might as well just use the latter.

Coherence: 3. The sapphire dragon has a boring sonic breath attack which causes fear, but its spell-like abilities do, in its defence, all make sense for a purely subterranean being - almost all being to do with the manipulation of stone and the generation of light.

Overall: 1.666

Topaz Dragon

Evocativeness: 4. A seacoast dragon is a nice idea and there are touches of genuine creativity on display, here: the image of a topaz dragon diving down into the sea, gannet like, to catch giant squid approaches genius. 

Usability: 4. A powerful 'boss-type' coastal monster is in itself useful, but the topaz dragon entry also adds an extra dimension to a hex map or dungeon by suggesting the entrances to their lairs are normally below the waterline, implying all manner of interesting logistical challenges.

Coherence: 4. Topaz dragons have various suitable water manipulation abilities and, impressively, the designers resisted the temptation to give them a fire-hose style breath weapon. Instead, unlike whites (which are from cold places and therefore breathe cold), topaz dragons have a breath attack which it actually makes sense for them to have - a dehydration cone. Yes, I buy it.

Overall: 4

Brass Dragon

Evocativeness: 2. I like the brass dragon illustration in the 2nd edition MM very much; it is redolent of a dimetrodon and to my eye is unusually distinctive amongst the other phoned-in dragon illos. That's where the evocativeness stops though, really; as with crystal dragons, we're left with the conclusion that a talkative possessor of useful information is really something for a game with a 'plot'. Also, as petty as it is, I find myself objecting to metallic dragons being identified with alloys rather than elements. Gold, silver and copper I am fine with. Brass and bronze, no thank you.

Usability: 2. I smell another rat here, in that much of the text of the entry for brass dragons is dedicated to explaining how, as inveterate bores, they use their abilities to capture victims so that they can keep them as conversation partners. This is vaguely suggestive to me of comic-relief style shenanigans; I'm not a fan.

Coherence: 3. Having a sleep cone breath weapon and a heat cone breath weapon make a sort of sense given what else we are told about brass dragons, and the abilities are a nice package for an 'arid plain' dweller. Being able to summon djinnis is also a solid idea.

Overall: 2.333

Bronze Dragon

Evocativeness: 3. We here find ourselves back in the 'friendly and talkative' arena, and the comments I made with respect to crystal dragons also apply here. With that said, however, the bronze dragon entry is much more interesting than the crystal one, with its hints about sunken treasure, shipwrecks, and aquatic lairs. There is much to like about this.

Usability: 4. There is a good deal of explanation in the entry about how to deploy bronze dragons in an encounter, and many reasons provided to include them in a hex map and ways to integrate them with the wider locality (they like shipwrecks; they ally with dolphins; they like pearls; etc.). This is a dragon type one could see oneself straightforwardly placing within a campaign region.

Coherence: 4. The combination of lightning and repulsion gas as breath weapons is an odd one (what even is 'repulsion gas'?) but the spell-like abilities all work well with what we are told about the dragon in the text. We're left with the impression of a coast-dwelling hunter, identifying prey with ESP, confusing them with fog, summoning storms to subdue them, and so on. This works.

Overall: 3.666

Copper Dragon

Evocativeness: 3. One's eyes begin to roll the instant one reads the words 'pranksters, joke tellers and riddlers' in any monster entry, least of all that of a dragon. But I will stick up for the position that at least in principle there is a fairy tale-ish, folklorish aspect to TSR-era D&D which it would be a shame to denigrate too much, and a riddling dragon is perfectly in keeping with the traditions of the genre. In that sense, copper dragons are ok by me.

Usability: 3. We have the intrinsic problem with all good dragons, which is that their existence seems to pre-empt conflict of any kind emerging with the PCs. But the copper dragon entry is well written and highly suggestive in the way it describes the tricky way that the monster operates, particularly in a fight.

Coherence: 4. The breath weapons and spell-like abilities nicely build the picture of a monster with a taste for the construction of mazes and the desire to slow and confuse intruders rather than killing them outright.

Overall: 3.333

Gold Dragon

Evocativeness: 4. As I said somewhere earlier on, I'm not of the opinion that D&D should be about unrelenting hostility, and there is definitely a space for openly and declaredly 'good' monsters, especially if - as with the gold dragon - they communicate an atmosphere of standoffish 'awesomeness' in the real sense of the word. I also like the vaguely 'Asian dragon' feel of the way the creatures are presented, from the art to the personality and abilities; the designers were clearly tapping into a distinct and distinctly non-Tolkienesque folk idea about dragons, here.

Usability: 3. Gold dragons are tailor-made to take on the role a 'quest dispenser' or possibly a wise adviser or font of helpful knowledge. Fine; there is a significant place for the latter, at least, in any sandbox campaign.

Coherence: 3. Again, there is a sense here that the designers were going for an 'Asian' feel here, as many of the gold dragon abilities are to do with luck and fortune. Makes sense, but it goes alongside a commitment for a Tolkienesque 'greedy dragon on a pile of treasure' motif that muddies the waters - gold dragons also breathe fire, and love gems.

Overall: 3.333

Silver Dragon

Evocativeness: 2. Silver is a poor man's version of gold, and so it is fitting that silver dragons come across as a poor man's version of gold dragons. They are yet another kind, helpful, and wise yet potent being. I apologise, but it gets a bit boring.

Usability: 3. Much the same applies for gold dragons as for silvers. Silver dragons seem created to play the role of quest dispense or, worse, GMPC. But the 'font of helpful knowledge' role is an important one.

Coherence: 3. Silver seems to be conflated here with cold, winds and weather - presumably because silver is like white and 'feels' like it has some connection or affinity to ice and snow. Why would a flying creature need to feather fall, though? 

Overall: 2.666

Brown Dragon

Evocativeness: 4. Something different is going on here - a wingless monitor-lizard affair, which digs deep in desert sands to wait for prey. Is this taking liberties with the very concept of dragonhood? Possibly, but coming after the good dragons in the list, it nonetheless feels refreshing.

Usability: 2. Brown dragons are another desert monster, which works in their favour, but the text only really suggests they exist to be killed and/or burgled. This is too easy, and we already have plenty of alternatives for that job.

Coherence: 4. It lives in the desert. It breathes a sand spray. Its spells allow it to create sandstorms, summon earth elementals, create water, etc. The only criticism is that this is perhaps too 'on the nose'.

Overall: 3.333

Cloud Dragon

Evocativeness: 4. Another 'Asian' dragon, which I like, and one which feels pleasingly 1980s for some reason, perhaps because whenever I think of creatures living in clouds my mind is drawn inexorably to Cloud City on Bespin. 

Usability: 2. Of course, the mileage here very much varies depending on how likely it is that the PCs will for some reason be visiting magical cloud islands. Cloud dragons, we are told, are reclusive and have contempt for beings that can't fly. Is it, then, likely that one will be able to find a use for one?

Coherence: 5. It lives in clouds; it can control weather, call lightning, produce fog, create water...the cloud dragon is in this respect the complete package.

Overall: 3.666

Deep Dragon

Evocativeness: 4. In some respects, the deep dragon is bland - simply an Underdark version of any of the standard 'evil' chromatic types. But a distinctive niche is suggested (roaming hunter) and the shapechanging abilities - into a human or giant snake - are a nice touch.

Usability: 4. Lots to play with here - deep dragons can appear as powerful laired monsters guarding treasure hoards, but also as roving dangers across a hex map or within a dungeon, or even perhaps as significant NPCs-in-disguise in an urban campaign. 

Coherence: 2. Deep dragons' abilities are a bit of a random assortment - levitate, free action, telekinesis, disintegrate, etc., but I suppose the idea is to imagine the magical toolkit an Underdark explorer would need and work from there. The tail wags the dog a bit, in other words. And I'm unconvinced as to where a corrosive gas breath weapon really fits in.

Overall: 3.333

Mercury Dragon

Evocativeness: 4. Mercury dragons are, well, mercurial. This is a bit painful. But it also makes for something a bit different - unpredictable, capricious, chaotic, and irrational rather than wise, cunning, aloof, etc.

Usability: 2. I have a hard time thinking about where a mercury dragon could fit into a campaign except as something with a lair on the hexmap or within a large dungeon - simply as an alternative to one of the many other kinds of dragon that could fulfil the same essential purpose. 

Coherence: 3. A beam of light 'breath' weapon is an interesting idea, but I'm not sure what it really has to do with mercury. The spell-like abilities, though, seem to derive from mercury's reflectivity and changeability, and work well as a coherent whole on those terms.

Overall: 3

Mist Dragon

Evocativeness: 3. Taken in isolation, the mist dragon is a nice idea - a moody, mysterious, brooding philosopher with a vaguely 'Asian' vibe. But taken alongside the other dragon types, it must be said that it simply feels too close conceptually to the cloud dragon. 

Usability: 4. The mist dragon's primary use case is obvious: a source of wisdom that must itself be sought in a difficult, dangerous, hidden location. It sees and knows all, but is only willing to share its knowledge for a price, and is hard to find. This works: the mist dragon is to all intents and purposes Dagobah-era Yoda.

Coherence: 3. A scalding vapour breath attack fits very well. The other abilities, though, are too easy - water breathing, wall of fog, solid fog, etc. 

Overall: 3.333

Shadow Dragon

Evocativeness: 4. The shadow dragon is a cheesy concept, but a sound one. It is also one of those cases in which the name of a monster more or less communicates everything you need to know about it. Shadow dragon. Instantly, on reading those two words, one knows exactly what the creature is and what it does.

Usability: 3. The shadow dragon clearly is meant to occupy the 'dragon at the bottom of the dungeon' role, and in that regard, although it is one dimensional, it obviously fits in nicely. I especially like the idea of one lurking at the base of a megadungeon as a kind of final 'boss'.

Coherence: 5. One has to say that the shadow dragon is almost the pinnacle of a high concept monster. The name sets out the stall. And everything flows from there - the behaviour, the abilities, the breath weapon, and so on). It's a dragon which embodies shadow, lives in the dark, and uses it to its advantage. Great.

Overall: 4

Steel Dragon

Evocativeness: 4. A dragon which likes to pose as a human being (presumably in secret) and lives typically in an urban setting; this is different, and I like the concept. I must however be scrupulously fair and consistent - there is, as I earlier said, something deeply illegitimate about metallic dragon types deriving from alloys. 

Usability: 3. Steel dragons make sense really in only one role - as interesting NPCs in a city-based campaign, or as a prominent figure in a major urban settlement on a hex map. I like that role, but it is very one-dimensional. 

Coherence: 5. The steel dragon's abilities and breath weapon map perfectly onto the role envisioned for the monster. It can create toxic gas in pre-determined volumes, big or small, so as to be the perfect poisoner or assassin; it can polymorph itself almost at will; it can use magic to dominate, persuade, befriend or command. It all fits together like a jigsaw.

Overall: 4

Yellow Dragon

Evocativeness: 2. The raison d'etre of the yellow dragon is that there ought to be yellow dragons because yellow is a colour. (On this basis, should there not also be a purple one?) This is weak. Yellow dragons, we are told, are 'solitary and secretive'. This is weak, too.

Usability: 2. Yellow dragons are essentially a mixture of browns and blues in terms of their abilities and MO. I can't help but feel that three types of dragon which live in the same environment and do more or less the same thing is overkill.

Coherence: 3. The only thing to say here is that yellow abilities are like those of browns or blues, and that the tone is once again 'more of the same'. It all makes sense; but it is uninspired.

Overall: 2.333

The Official Ranking, Best to Worst

1 - Red

2 = - Topaz

2 =  - Steel

2 = - Shadow

5 = - Cloud

5 = - Bronze

7 = - White

7 = - Copper

7 = - Gold

7 = - Brown

7 = - Deep

7 = - Mist

13 = - Blue

13 = - Green

13 = - Emerald

13 = - Mercury

17 = - Silver

17 = - Black

19 = - Yellow

19 = - Brass

21 = - Amethyst

21 = - Crystal

23 - Sapphire


  1. Blue dragons obviously have a "mirage" thing going. blue like an oasis in the desert, hallucinations are mirages. still doesn't explain the fucking lightning, tho. but they're a bit more coherent vibes-wise than you give them credit for imo

    1. Possibly lightning is a reference to static electricity building up during sandstorms?

    2. I would suggest blue is because of the sky. They are hard to pick out in the endless blue sky. Lightning fits with thunderstorms and the static found in a sandstorm.

      I imagine a family of blue dragons hunting just behind a thunderstorm, with momma tearing apart a building so her younglings can crawl inside and dig out the juicy people hiding inside. The rest of the community may not even know what happened.

      I can also see a large blue dropping out of the sky and breaking so that its wings whip up a nasty localized sandstorm. Blinding a caravan trapped out in the open long enough for it to tear into a wagon or take off with the draft animals. If it used its lightning breathe the survivors may not even known they were hit by a dragon allowing it to hunt along the same caravan trail for a long time.

    3. The electricity thing makes me think they could use it to blend in. The dragon holds a charge to make dust and sand cling to it. Maybe it all comes off when it uses its breath weapon? You would know the breath weapon was ready when the dragon blends in again.

  2. Oh yes, we absolutely need a Purple Dragon! What would it's stats and description bei? Of course, an overall rating of 4 should be achieved.

    1. I have a vague feeling that there is a purple dragon in one of the old Dragon magazines.

    2. Yes, the Purple Dragon was in an article in Dragon (#65) that filled out the color wheel. The purple dragon, mixing blue and red, breathed a lance of energy (fire + lighting = plasma?).

  3. The purple dragon has become the purple worm. A dragon consumed by its desire to horde all, to ingest the world. Reduced to a mouth and a tube of gargantuan size, the other dragons no longer acknowledge its place in dragonkind.

  4. I always liked blues breathing lightning and living in deserts. I think blue - sky - storm - lightning - desert winds / sandstorms. I also think of the electrical wormsign from Lynch's Dune. Definitely an impressionistic grab-bag, but it worked for me.

  5. "A beam of light 'breath' weapon is an interesting idea, but I'm not sure what it really has to do with mercury."

    I assume it's a reference to mercury's reflectivity, which you mention in the next sentence. It's not exactly brilliant, but it's not completely random either.

    1. I guess so, yes. I think it would be possible to do something interesting with a mercury dragon which is more to do with the liquidity of mercury than its reflectiveness.

  6. Mockman here... I once did an (unofficial) family tree for the Wizards website connecting all D&D dragons and dragon-types I was aware of, from 1st through 4th edition. Unfortunately I didn't really draw much in the way of illustration to make it interesting, but someone put it on Pinterest here:

  7. Promptly reminded of this string of posts, which seem to hang together better.

  8. It feels to me that there is a missed opportunity in not tying the silver dragon to the D&Dish properties of silver. There should be some interesting interactions with lycanthropes and undead; imagine a good dragon with werewolf servants! Perhaps by extension there should be some association with mirrors and the moon. Maybe silver dragons come from the moon?

    1. Ooh, nice idea! Perhaps a Silver Dragon can keep the lycanthropy curse under some measure of control or arrest, and so sufferers tend to seek them and indeed serve them. Silvers can be a sort of "quasi-evil harnessed to good" to complement the Golds' more judgemental benevolence.

    2. The Blacks' breath weapon being acid is, I assume, tied to the idea of corrosion, of caustic rot, in keeping with the swampy terrain they're associated with. Black Dragons break down the environment around them into an overly-decomposed sludge.

    3. Yeah, the silver as the sort of 'Dark Knight' of good dragons actually makes a lot of sense to me.

  9. This is the kind of whimsical commentary that no one asked for or needs, but I still enjoyed reading. Therefore, blogs. Cheers.

    1. I thought it would be a quick half hour to write but it took absolutely ages.

    2. haha. blogging in a nutshell.

  10. This is the kind of post that reminds me of why I fell in love with the RPG blogosphere.

    It's a shame that green and black are so muddled, because they're sharing all of my favorite dragon ingredients. If I had to make them more distinct, I would reassign black dragons to old ruins and battlefields as their favored terrain, since you're right that green dragons deserve to be the poisonous swamp dragon.

    1. I've never minded the current Black-Green distinction. To me it makes sense. I read the Blacks as representing corrosion, degeneration, toxicity in an entropic sense. They break down the ecosystem around them into sludge, into acidic, unpalatable water and ooze, just as they spitefully seek to undermine any order or decency. Greens, by contrast, are toxicity in the sense of complexity, of blooming flowers and adaptive poisons, of life rather than death. They prefer vibrant, thriving ecosystems, much as they prefer more complex mental pursuits, being the scholars of the chromatic dragons.

      Blacks are entropic, greens are vibrant. Both are toxic.

    2. You are tempting me to do my own reimagining of all the dragon types....