The bodies of Styx dragons were long and serpentine. Their slimy scales ranged in color from dark brown to rusty red and their eyes glowed with a sickly yellow light.
Styx dragons were completely adapted for life underwater. Although capable of living indefinitely on dry land, they were incapable of flight and their short webbed limbs were ineffective for movement on the ground. However, they excelled at swimming and underwater combat and hunting.
Due to their atrophied limbs, Styx dragons could not effectively attack with their claws. Instead, they had adapted their long bifurcated bladed tails to be devastating cutting and constricting weapons. Both their tails and their bites infected their targets with a disease known as Stygian wasting, which caused flesh to rot away and hair to fall out over a period of several days.
They possessed two breath weapons: a cone of acid that had a slow, lingering effect, and a cone of gas that drained the intelligence of any creature hit by it. They could also innately cause effects similar to the control water, curse water, deeper darkness, feeblemind, fog cloud, hold monster, horrid wilting, mind fog, and stinking cloud spells.
In addition, Styx dragons also had the ability to summon giant fiendish water creatures such as crocodiles, giant octopuses, sharks, squids, tojanidas, or even water elementals, in an effect similar to the summon monster VIII spell.
Styx dragon lairs were usually dug on the muddy banks of the Styx, or, if brought forcefully into the Prime Material plane, any place with foul water. They could be found alone or in families as they raised their young. Clutches of young Styx dragons were also common.
They could be found on the first layer of all Lower planes of the Great Wheel cosmology, following the course of the Styx, as well as all the Fiendish planes of the World Tree cosmology, following the course of the River of Blood. Styx dragons were very rarely found on Toril.
- Andy Collins, James Wyatt, and Skip Williams (November 2003). Draconomicon: The Book of Dragons. (Wizards of the Coast), pp. 187–189. ISBN 0-7869-2884-0.
- Richard Baker (October 1995). Monstrous Compendium Planescape Appendix II. Edited by Karen S. Boomgarden. (TSR, Inc.), pp. 92–93. ISBN 0-7869-0173-X.
- Eric L. Boyd, Eytan Bernstein (August 2006). Dragons of Faerûn. (Wizards of the Coast), p. 11. ISBN 0-7869-3923-0.
- Julia Martin, Eric L. Boyd (March 1996). Faiths & Avatars. (TSR, Inc.), p. 153. ISBN 978-0786903849.
- Eric L. Boyd (September 1997). Powers & Pantheons. Edited by Julia Martin. (TSR, Inc.), p. 86. ISBN 978-0786906574.
- Wolfgang Baur (August 2007). “Enemies of My Enemy”. In James Jacobs ed. Dungeon #149 (Paizo Publishing, LLC), pp. 84–85.
Chromatic dragons: Red • Black • Blue • Green • White • Brown • Gray • Purple • Pink • Salt • Yellow
Gem dragons: Amethyst • Beljuril • Emerald • Sapphire • Topaz • Crystal • Obsidian • Ruby
Neutral dragons: Amber • Jacinth • Moonstone • Pearl
Lung dragons: Chiang lung • Li lung • Lung wang • Pan lung • Shen lung • T'ien lung • Tun mi lung • Yu lung
Planar dragons: Adamantine • Astral • Battle • Blight • Chaos • Ethereal • Hellfire wyrm • Howling • Mirage • Oceanus • Pyroclastic • Radiant • Rust • Shadow • Styx • Tarterian
Epic dragons: Force • Prismatic
Catastrophic dragons: Earthquake • Volcanic
Miscellaneous dragons: Cobra • Dzalmus • Mist • Radiant • Rattelyr • Song • Vishap
Draconic transformations: Air • Ascendant • Brainstealer • Hidecarved
Linnorms: Corpse tearer • Dread • Stygian
Drakes: Ambush • Black firedrake • Dragonne • Elemental (Earth • Fire • Ice • Magma • Ooze • Smoke • Water) • Felldrake (Crested • Spitting) • Greater • Guard • Mind • Portal • Rage • Space • Vulture
Dragonets: Crow's-nest dragon • Draken • Faerie dragon • Firedrake • Pseudodragon
Dragonbloods: Draconic creature • Dragonborn of Bahamut • Dragonspawn
Drow-dragon (shadow) • Drow-dragon (deep) • Half-dragon • Kobold (Dragonwrought • Urd) • Weredragon • Zar'ithra • Zekyl
Undead dragons: Dracolich • Dragonwight • Ghost • Hoarder • Rathrea • Vampiric • Zombie