Now I'll show you the guide I'm working on as a result of this exercise. Note that this is meant to be a "self" guide, and as such I'm not saying this is the only way to write dragons in your story or setting, I'm just saying this is one way I enjoy and I feel I won't mess up a story I make if I follow it.
About Dragons
Shared rules: -This should work primarily as a guide, and as such the rules are flexible enough to allow for adaptation, with many of the rules reflecting just that;
- Intelligence and ability to communicate are proportional in each individual, but not necessarily tied;
- Shapes of the creatures are suggested, but no hard limit is set on how to portray them;
- Human shape refers to the ability or characteristic of an individual displaying physical human traits or complete human form, the specifics being up to the person portraying them;
- Every individual of any kind should have a low chance, or regional characteristic, of featuring an ability from another kind, but said ability shall not be one its actual kind is averse to;
- Since this guide is expected to be used for fantastical settings, an individual's chances of being able to display supernatural prowess is suggested, but as it is tied to the intelligence levels of each individual it can also be adapted into different types of activities;
- This guide uses frequency of events as descriptions for how often a kind of individual will display a trait, but it should be noted that the terms "almost never" and "almost always" relate to how this guide is never absolute about defining most characteristics, and as such it predicts the possibility of exceptions to the rules.
About hierarchy: A grass snake is to a drake the same that a monkey is to a man; while a man is to god the same that a drake is to dragon.
That said, due to the implementation of the suggestions in this guide being mostly geared towards use in games, there will be a common rank and an experienced or advanced rank akin to how you would compare "power levels" of mythological creatures. Think of them as my alternative to the Dungeons & Dragons drake-to-dragon hierarchy.
Kinds
•Drake The most popular form of this creature, the drake fills in the role of the medieval, christianized traditions of dragon tales, this one being the most vile and "chaotic" kind. Similar to D&D's red dragon.
- Abilities: fire breathing is its bread and butter, but its physical strength and endurance are often enough for overpowering its foes or prey;
- Resistant to fire | Averse to cold;
- Rarely intelligent;
- Almost never learn spells;
- Shapes: winged lizard stereotype, with either a long or shorter, more "fit", neck, often featuring brown or somewhat red scales;
- Almost never displays human shape.
•Advanced Drake - Likely intelligent, still rarely communicates with humans;
- May learn spells, however almost never finds benefit in using them due to a low affinity to such activities.
•Wyrm The wyrm fills in the gap that exists in descriptions of european dragons older than the Christian tradition, such as Níðhöggr, and as result being somewhat "forgotten" amidst all the other more prevalent traditions of this kind of being; it still isn't the sea variant that this name is commonly associated with, however. Reaches for the white dragon of D&D fame, sometimes also called ice dragon, but under the rules in this guide it may very well be used as an alternative to the drake.
- Abilities: relying mostly on agility and physical strength, this class isn't as reliant on a characteristic breath – note that it is possible for one to breath cold/ice - but may be able to create a cold aura if it isn't reliant on an aggressive breath already; It should be noted that its physical prowess isn't as relevant as those of the drake and even the wyvern; May either be able to fly or dig depending on the presence of wings;
- May be resistant to cold;
- Rarely intelligent;
- May learn spells;
- Shapes: while it may be simply portrayed as a drake it should still favor longer necks, however it doesn't necessarily need to be winged or be "lizard-like"; often features brown, light green or light blue scales scales;
- Almost never displays human shape.
•Advanced Wyrm - Due to higher intelligence it will often alternate its attacks based on its agility/mobility and its aggression through elemental effects, making it a largely more meaningful threat than its common variant especially inside areas that grant it advantageous positions;
- Almost always intelligent, still almost never communicates with humans.
•Wyvern Present in several images of heraldry, the wyvern here fills the whole of the less intelligent member of the dragon kind, allowing the writer or game designer to introduce a type of dragon that can be tamed, for example. Closer to the blue dragon of D&D fame.
- Abilities: highly reliant on flight and attacks based on opportunities, often making good use of its ability to inflict physical damage, the wyvern lacks a characteristic breath;
- Resistant to lightning;
- Almost never intelligent;
- Almost never learn spells;
- Shapes: often may be the blue or brown scaled two-legged winged serpent commonly seen in heraldry and described as a wyvern;
- Almost never displays human shape.
•Advanced Wyvern - Rarely intelligent.
•Viper Vipers come from the stereotype of both the vouivre/guivre and the drakaina. These are supposed to be the more venomous variants of the dragon kind. Analogue to the black dragon of D&D fame.
- Abilities: while its physical prowess is still higher than those of most men, they are hard to compare to those of most other kinds, and as such vipers are more reliant on poisonous breaths, auras, and even deceptions;
- Resistant to poison;
- Often intelligent;
- May learn spells;
- Shapes: vipers are most likely to alternate red and black scales, often featuring wings unlike those of other dragon kinds; in addition, their appearance may be intertwined with the human form; alternatively, the writer/master may choose to just depict them as regular dark scaled wyrms instead, which is perfectly acceptable depending on setting;
- Often displays human shape.
•Advanced Viper - Almost always intelligent;
- Almost always displays human shape.
•Serpent These are the original kind, often water dwellers and prevalent on rivers and lakes. The writer needs, however, to make the distinction between the sea serpent and dragons if the intention of exploring the genesis of any given setting exists, and surely, this distinction may or may not exist. This stereotype doesn't fit any specific fictional stereotype I'm aware of, but it's closer to the drakon/drakaina and the naga. Again, it is possible to omit this kind in most works due to the similarities with the Viper described above, which is a more versatile class.
- Abilities: without a characteristic breath and rarely reliant on elemental effects, the serpents find the characteristic of being water bound many of the times as a big disadvantage that counters their ability to cause the most physical damage of all dragon kind;
- May be resistant to poison;
- Rarely intelligent;
- May learn spells;
- Shapes: as a serpent, they almost always lack limbs even if the ability of flight is present; in addition, their appearance may be intertwined with the human form;
- Almost never displays human shape.
•Advanced Serpent - Likely intelligent;
- Shapes: may gain additional heads and maybe limbs;
- May display human shape.
•Long Probably the most important kind of dragon outside of the popular fire breathing dragons, this guide shouldn't leave these out.
- Abilities: rarely relies on physical strength, using mostly elemental effects for all of its actions, including the ability to cause thunders, which may or may not be interpreted as the lightning breath;
- Resistant to lightning;
- May be intelligent;
- May learn spells;
- Shapes: very much like the serpent, but may feature small limbs; almost never features wings;
- Rarely displays human shape.
•Advanced Long - Almost always intelligent;
- May display human shape.