Virtually all dragons revere Io, Chronepsis, and Zorquan. Io’s priesthood is rare, although all dracoforms are his children and he welcomes them all. Similarly, the death of all dracoforms are the realm of Chronepsis, and he may call any of them to his service. Finally, even though all dracoforms may look to Zorquan for guidance and assistance in improving themselves and their skills, Zorquan only accepts true dragons into his service, and his priests will refuse to train unusual dragons (Faerie Dragons, Dracohydras, etc.). Rogue dragons may worship, and become priests of, virtually any deity; for example, a Gold Dragon who becomes hateful of life may turn to Faluzure, or a pyromaniacal Faerie Dragon may turn to Garyx’s faith. Generally, dragons who are only slightly different in alignment (NG rather than CG for example) are just considered odd or strange, while more significantly different (CE rather than CG) are considered true rogues; dragons will react to such rogues in much the same way as they would react to dragons who are normally of that alignment. The following list includes the primary deities dragons would worship, as well as some deities favored by rogues. Those deities bolded are the most common favored deities. Some of the details are likely to change.
Chromatic Dragons (and close relatives):
Black Dragons: Per Council of Wyrms, Black Dragons cannot become dragon-priests. As an option, they may be able to become specialty priests late in life. Astilabor, Task, Tiamat, and Zorquan would be their favored deities.
Blue Dragons: Full range of options available. Arcanic, Astilabor, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Brown Dragons: Full range of options available. Astilabor, Elemtia, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Deep Dragons: Full range of options available. Astilabor, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities, although a significant number of deep dragons have switched to worship Drow deities.
Green Dragons: Full range of options available. Arcanic, Astilabor, Elemtia, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Red Dragons: Full range of options available. Astilabor, Elemtia, Garyx, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
White Dragons: Per Council of Wyrms, cannot become dragon-priests. As an option, they may be able to become specialty priests late in life. Astilabor, Task, Tiamat, and Zorquan would be their favored deities.
Yellow Dragons: Per Dragon #263 (The Western Wyrms), cannot become dragon-priests. I feel it is reasonable to disregard this. Astilabor, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Metallic (and close relatives):
Adamantite Dragons: Planescape holds there to be just one Adamantite Dragon; MC08 infers it is a whole species. If used as a whole species, they would have the full range of options available. Arcanic, Astilabor, Bahamut, Kereska, Rais, Tamara, and Zorquan would be their favored deities. Very rare rogues might favor Garyx.
Brass Dragons: Full range of options available. Aasterinian, Astilabor, Bahamut, Elemtia, Hlal, Kereska, Tamara, and Zorquan would be their favored deities.
Bronze Dragons: Full range of options available. Arcanic, Astilabor, Bahamut, Kereska, Lendys, Rais, Tamara, and Zorquan would be their favored deities.
Copper Dragons: Full range of options available. Aasterinian, Astilabor, Bahamut, Elemtia, Hlal, Kereska, Tamara, and Zorquan would be their favored deities. Task would be common for rogues.
Electrum Dragons: Close relative of metallics; full range of options available. Arcanic, Astilabor, Bahamut, Elemtia, Kereska, Sardior, Tamara, and Zorquan would be their favored deities.
Gold Dragons: Full range of options available. Arcanic, Astilabor, Bahamut, Kereska, Lendys, Rais, Tamara, and Zorquan would be their favored deities. Rogue golds overwhelming are drawn to Garyx.
Mercury Dragons: Close relative of metallics; full range of options available. Aasterinian, Astilabor, Bahamut, Elemtia, Hlal, Kereska, Tamara, and Zorquan would be their favored deities.
Mithril Dragons: Close relative of metallics from the world of Radole in Spelljammer; reasonable to make them available elsewhere with some changes to their lifestyle. Full range of options available. Aasterinian, Bahamut, Elemtia, Garyx, Hlal, Kereska, and Zorquan would be their favored deities.
Silver Dragons: Full range of options available. Aasterinian, Arcanic, Astilabor, Bahamut, Hlal, Kereska, Lendys, Rais, Tamara, and Zorquan would be their favored deities.
Steel/Greyhawk Dragons: Close relative of metallics; full range of options available. Note the Monstrous Manual Steels are actually Greyhawk Dragons; the Steel Dragons of the Forgotten Realms are found in FOR1 Draconomicon and are slightly different, although the differences don’t alter their outlooks. Arcanic, Astilabor, Bahamut, Kereska, Lendys, Rais, Sardior, Tamara, and Zorquan would be their favored deities.
Weredragons: Close relative of metallics; full range of options available. Aasterinian, Arcanic, Astilabor, Bahamut, Elemtia, Hlal, Kereska, Lendys, Rais, Sardior, Tamara, and Zorquan would be their favored deities.
Gem Dragons:
Amethyst Dragons: Full range of options available. Arcanic, Astilabor, Kereska, Rais, Sardior, and Zorquan would be their favored deities.
Crystal Dragons: Full range of options available. Aasterinian, Astilabor, Elemtia, Hlal, Kereska, Sardior, and Zorquan would be their favored deities.
Emerald Dragons: Full range of options available. Arcanic, Astilabor, Kereska, Lendys, Sardior, and Zorquan would be their favored deities.
Sapphire Dragons: Full range of options available. Astilabor, Kereska, Lendys, Sardior, and Zorquan would be their favored deities.
Topaz Dragons: Full range of options available. Astilabor, Elemtia, Kalzareinad, Kereska, Sardior, Task, and Zorquan would be their favored deities.
Ferrous Dragons:
Chromium Dragons: Full range of options available. Astilabor, Elemtia, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Cobalt Dragons: Full range of options available. Arcanic, Astilabor, Elemtia, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Iron Dragons: Full range of options available. Arcanic, Astilabor, Bahamut, Garyx, Kereska, Lendys, Sardior, and Zorquan would be their favored deities.
Nickel Dragons: Full range of options available, although their lower intelligence compared to their brethren may indicate they cannot become priests. Astilabor, Elemtia, Task, and Zorquan would be their favored deities.
Tungsten Dragons: Full range of options available. Astilabor, Bahamut, Elemtia, Kereska, Tamara, and Zorquan would be their favored deities.
Oriental Dragons:
While likely offshoots of normal dragons (gold and/or jade the most likely origins), oriental dragons are members of the Celestial Bureaucracy; as such they are all essentially divine servants. As such, they do not become priests of the draconic gods.
Linnorms:
Norse dragons tend to be overpowered in general; while they have no restriction against becoming priests, it seems unlikely, and most will not appear in draconic deity entries. For those wishing to make use of them with the dragon gods (I recommend revising their Hit Dice and other statistics to bring them in line with the chromatic dragon), note that few would follow Zorquan, with most choosing Elemtia, Faluzure, Kalzareinad/Kereska, Task, or Tiamat, although flame linnorms would certainly worship Garyx. One could promote their unique archetype, the Corpse Tearer, to a deity, even though it is inspired by Nidhoggr. The other archetype, the Midgard Dragon (stated as being an offspring of the Midgard serpent), seems ill-suited to the role.
Space Dragons:
Moon Dragons: Full range of options available. Astilabor, Faluzure, Kalzareinad, Kereska, Task, Tiamat, and Zorquan would be their favored deities.
Radiant Dragons: Radiant Dragons receive far more priest spells than any other dragon, even dragon priests. Because of this, they have little incentive to become priests, although there is nothing preventing it. It seems likely that they get their spell spheres from one of the draconic gods’ specialty priests, however. Alternately, they may all be a form of draconic priest unique to their species. They are likely to follow virtually any deity, although Bahamut, Tiamat, and Sardior are the least likely. As they are especially prideful of their size compared to most other dragons; many may consider themselves perfected dragons, and would favor Zorquan. Other choices would fit their personality, with Aasterinian, Astilabor, and Kereska fairly common.
Stellar Dragons: Dwarfing even Radiants, these dragons have the full range of options available to them. Aasterinian, Arcanic, Kereska, Rais, Sardior, and Zorquan would be their favored deities.
Sun Dragons: Full range of options available. Aasternian, Arcanic, Astilabor, Bahamut, Elemtia, Garyx, Kereska, Tamara, and Zorquan would be their favored deities.
Mystaran Gemstone Dragons:
As these dragons are unique to Mystara, they do not become priests of the draconic pantheon.
Other Dragons:
Air Dragons: A non-undead emanation from the mind of a dead or near-dead dragon from Coliar, they cannot become priests, and no priests become Air Dragons.
Albino Wyrms: While intelligent, they are insane and have no spellcasting abilities. They cannot become priests. Note I recommend recalculating AC, MR, and breath weapon damage. If any worship the draconic deities, they would probably be Faluzure or Tiamat. Those who recognize their deficiencies and wish to surpass them would look to Zorquan.
Amber Dragons: Full range of options available. Elemtia, Kereska, Lendys, Sardior, Tamara, and Zorquan would be their favored deities.
Amphi Dragons: Crossbreed of Green and Sea Dragons from Krynn; if Sea Dragons are found on other worlds that have Green Dragons, Amphi Dragons are possible. Generally, few dragon-priests would be willing to teach them the ways of a priesthood, but becoming dragon-priests is theoretically possible. Faluzure, Task, and Tiamat would be their favored deities, while those who want to prove themselves to other dragons would favor Zorquan.
Astral Dragons: Unique to Krynn’s godly configuration; not suitable for use in other campaigns.
Brine Dragons: Fully aquatic dragon from Krynn; if found on other worlds they would have the full range of options available, although learning from non-aquatic dragons would be impossible, and they have no claws to manipulate objects. Of note, there is a powerful specimen on the Quasielemental Plane of Salt. Faluzure, Task, and Tiamat would be their favored deities.
Cerilian Dragons: Unique species found on Cerilia; all are Old age or older. Not suitable for use in other settings.
Cloud Dragons: Full range of options available. Arcanic, Astilabor, Elemtia, Kereska, Lendys, Sardior, and Zorquan would be their favored deities.
Crimson Dragons: Unique to Mystara, and not suitable outside the Savage Coast.
Dracohydras: Like White Dragons, they are not particularly intelligent, and likely cannot become dragon-priests. As an option, they may be able to become specialty priests late in life. Task, and Tiamat would be their favored deities, while those who want to prove they are true dragons would favor Zorquan.
Dracoliches (any species): Very few deities would accept them; Faluzure, Kalzareinad, and Tiamat would, while Task and Garyx might. No other deities would.
Faerie Dragons: Full range of options available, with some modifications. Aasterinian, Arcanic, Astilabor, Bahamut, Elemtia, Hlal, Kereska, Nathair Sgiathach, Rais, and Tamara would be their favored deities.
Fang Dragons: Full range of options available. Astilabor, Elemtia, Kalzareinad, Kereska, Task, and Zorquan would be their favored deities.
Fire Dragons: False dragons from Krynn, appearing during the Summer of Chaos.
Jacinth Dragons: Full range of options available. Aasterinian, Arcanic, Astilabor, Elemtia, Kereska, Lendys, Sardior, Tamara, and Zorquan would be their favored deities.
Jade Dragons: Said to be related to emerald dragons and oriental dragons; the former seems unlikely. Unlike other oriental dragons, they are not part of the Celestial Bureaucracy. Full range of options available. Aasterinian, Arcanic, Astilabor, Elemtia, Kereska, Lendys, Sardior, and Zorquan would be their favored deities.
Kodragons: Like the Astral Dragon, they are unique to Krynn’s godly configuration.
Mist Dragons: Full range of options available. Arcanic, Astilabor, Elemtia, Kereska, Sardior, and Zorquan would be their favored deities.
Moonstone Dragons: Full range of options available. Aasterinian, Arcanic, Astilabor, Elemtia, Kereska, Lendys, Nathair Sgiathach, Sardior, and Zorquan would be their favored deities.
Pearl Dragons: Full range of options available. Aasterinian, Arcanic, Astilabor, Elemtia, Kereska, Lendys, Sardior, and Zorquan would be their favored deities.
Prismatic Dragons: Full range of options available. Aasterinian, Astilabor, Elemtia, Kereska, Sardior, Task, and Zorquan would be their favored deities.
Rain Dragons (Tlalocoatls): Found in Maztica and perhaps other Mesoamerican-based settings; they all function as priests of Azul.
Red Hawk Dragon: Unique to Mystara, but it would not be unreasonable to find them outside the setting. Elsewhere, the full range of options would be available. Arcanic, Astilabor, Garyx, Hlal, Kereska, Lendys, Sardior, Tamara, and Zorquan would be their favored deities.
Rust Dragons: Not true dragons; cannot become dragon priests.
Sea Dragons: Krynnish dragons with a similar form as Dragon Turtles. As there is nothing specifically Krynnish about them, they might be found on other worlds. Full range of options available. Astilabor, Elemtia, Task, Tiamat, and Zorquan would be their favored deities.
Shadow Dragons: Full range of options available. Astilabor, Chronepsis, Faluzure, Kalzareinad, Kereska, Sardior, Task, and Zorquan would be their favored deities.
Shadowdrakes: Lower planar dragons found in infernal rivers. Some might have the desire to become priests, and there is nothing about them that indicates they cannot. Astilabor, Faluzure, and Task would be their favored deities.
Steppe Dragons (Dzalmauses): Not at all sociable, these three-headed dragons from the Hordelands of Toril are unlikely to be eligible to become priests. Elemtia, Faluzure, Tiamat, and Zorquan would be their favored deities.
Tylor: Crossbreed of evil dragons and hatori, the large crocodile-like reptiles from Krynnish deserts. Hatori are found in the Monstrous Manual, so Tylors might be found on other worlds as well. Seems unlikely many dragons would be willing to train them in the ways of becoming a priest, however. Aasterinian, Faluzure, Kalzareinad, Kereska, and Tiamat would be their favored deities, although many would be drawn to Zorquan as a means of proving they are above their mixed parentage.
Vishaps: Wingless dragons from arid or tropical regions, originally found in Al-Qadim. Not very likely to become priests, but the possibility exists. Astilabor, Faluzure, Task, Tiamat, and Zorquan would be their favored deities.
Half-Dragon Priests
Only Bahamut and Tiamat allow half-dragons to become specialty priests, and only allow them among their humanoid priests. Half-dragons may become clerics of any draconic deity except Zorquan, although this is still quite rare. Half-dragons of other classes may also worship the draconic deities (half-dragon bards especially favor Hlal, for example) and join the clergy.
Don’t you thing Golds would also favor Kereska, since they study spells?
They’d often prefer Arcanic, as he is lawful rather than chaotic. They’d still pay homage to her, though, which is why she’s in the list for golds.
I see… And don’t you think Arcanic would be among their favored gods, then?
I think when golds get passionate about a cause, it tends to be justice, not magic. Some will certainly get passionate about magic, which is why those other deities are in the list, but it isn’t “typical” (as typical as a dragon getting passionate about religion can be).