Adders were scaled and highly venomous serpents, sometimes growing big enough to swallow one or multiple humanoids at a time. Some adders' scaled were colored black, banded with thin grey stripes. Their heads had horn-like ridges above the eyes, the most distinct feature of the adder. Their venom glands appeared as slight bulging beside the creatures' ear holes and fed deadly venom into their sharp fangs. Like other snakes, they had forked tongues that served as a tactile sensory organ.
Amphisbaena were considered close relatives of adders or very close resembling them in the markings' patterns but possessed a much deadly venom.
- Black adder
- Black sand adder
- Common adder
Common adders could be found throughout Serpent Hills in the Western Heartlands. The species of the common adder were known fo their sexual dimorphism. Male adders had greenish-gray scales with angular black patterns on their scales, while females had reddish-brown scales and darker black patterns. A bite of a common adder was venomous but not lethal for most beasts and humanoids of medium size. Their venom caused nausea and vomiting and could incapacitate a creature for up to for days after a bite.
- Flame adder
- Giant snow adder
- Puff adder
Beyond the world of Toril, adders could be found on the worlds of Athas, Aebrynis, and Eberron, as well as on the third layer of Arborea, Pelion, adders could be found inhabiting the desert realms of Amun-thys.
The spell fist of the adder transformed the caster's arms into adder snakes allowing them to deal devastating unarmed attacks with the serpents' bites. The material component of the spell was the shed skin of a venomous snake, such as adder, washed in tears.
- Adder's root was a highly poisonous and deadly plant.
- 1328 DR was named the Year of the Adder.
- The five-headed whips of the drow priestesses of Lolth had living adders as the part of the weapons.
- Clerics of the god Set could turn into giant adders via the incarnation of evil divine spell.
- Curse of the Azure Bonds • Shadowdale • Caravans
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- Prophet of Moonshae • Star of Cursrah • Dissolution • Venom's Taste • Vanity's Brood
- Referenced only
- Pool of Radiance • Pool of Twilight • Passage to Dawn • The City of Splendors: A Waterdeep Novel • Lady of Poison • The Halls of Stormweather • Shadow's Witness • The Rage • The Rite • Twilight Falling • Elminster in Hell • Elminster's Daughter • Resurrection • Darkvision • Frostfell • The Fall of Highwatch • Cry of the Ghost Wolf • The Bargain
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- Mike Mearls, Stephen Schubert, James Wyatt (June 2008). Monster Manual 4th edition. (Wizards of the Coast), p. 240. ISBN 978-0-7869-4852-9.
- Skip Williams, Jonathan Tweet, Monte Cook (July 2003). Monster Manual v.3.5. (Wizards of the Coast), p. 280. ISBN 0-7869-2893-X.
- Rick Swan (1994). Al-Qadim: Caravans: Adventure Book. (TSR, Inc), p. 9. ISBN 1-56076-903-3.
- James Butler, Elizabeth T. Danforth, Jean Rabe (September 1994). “Explorer's Manual”. In Karen S. Boomgarden ed. Elminster's Ecologies (TSR, Inc), p. 7. ISBN 1-5607-6917-3.
- Doug Stewart (June 1993). Monstrous Manual. (TSR, Inc), p. 320. ISBN 1-5607-6619-0.
- Tim Beach (October 1995). “The Serpent Hills”. In Julia Martin ed. Elminster's Ecologies Appendix II (TSR, Inc), p. 7. ISBN 0786901713.
- Lisa Smedman (March 2004). Venom's Taste. (Wizards of the Coast), chap. 15. ISBN 0786931663.
- Ed Greenwood, Eric L. Boyd, Darrin Drader (July 2004). Serpent Kingdoms. (Wizards of the Coast), p. 147. ISBN 0-7869-3277-5.
- Mike Pondsmith, Jay Batista, Rick Swan, John Nephew, Deborah Christian (1988). Kara-Tur: The Eastern Realms (Volume I). (TSR, Inc), p. 62. ISBN 0-88038-608-8.
- Sean K. Reynolds, Steve Miller (2000). Into the Dragon's Lair. (Wizards of the Coast), p. 91. ISBN 0-7869-1634-6.
- Jeff Crook, Wil Upchurch, Eric L. Boyd (May 2005). Champions of Ruin. (Wizards of the Coast), p. 108. ISBN 0-7869-3692-4.
- Lisa Smedman (March 2006). Vanity's Brood. (Wizards of the Coast), chap. 1. ISBN 0-7869-3166-3.
- Richard Baker (lead), Robert J. Schwalb Dark Sun Campaign Setting. Edited by Michele Carter (lead), Greg Bilsland, M.Alexander Jurkat, Ray Vallese. (Wizards of the Coast), chap. 5, p. 159. ISBN 978-0-7869-5493-3.
- Wolfgang Baur Warlock of the Stonecrows. Edited by Dan Wenger. (TSR, Inc.), p. 39. ISBN 0-7869-0185-3.
- Bill Slavicsek Eberron Campaign Setting. Edited by Michelle Carter. (Wizards of the Coast), p. 194. ISBN 620-86400-001-EN.
- Wolfgang Baur and Lester Smith (1994-07-01). “The Travelogue”. In Michele Carter ed. Planes of Chaos (TSR, Inc), p. 55. ISBN 1560768746.
- Lisa Smedman The Awakening. Edited by Richard Pike-Brown. (TSR, Inc.), p. 23. ISBN 1-56076-883-5.
- R.A. Salvatore (August 2008). Passage to Dawn. (Wizards of the Coast). ISBN 978-0786949113.
- Mark Middleton et al (January 1998). Wizard's Spell Compendium Volume Two. (TSR, Inc), pp. 371–372. ISBN 978-0786906642.
- Douglas Niles (March 1992). Prophet of Moonshae. (TSR, Inc), chap. 16. ISBN 1-56076-319-1.
- Andrew Finch, Gwendolyn Kestrel, Chris Perkins (August 2004). Monster Manual III. (Wizards of the Coast), p. 96. ISBN 0-7869-3430-1.
- Mike Mearls, Jeremy Crawford, Christopher Perkins, James Wyatt (2014). Dungeon Master's Guide 5th edition. (Wizards of the Coast), p. 188. ISBN 978-0786965622.
- Ed Greenwood (January 1993). Volo's Guide to Waterdeep. (TSR, Inc.), p. 66. ISBN 1-56076-335-3.
- Template:Cite book/Realms of the Dragons/Penitential Rites
- James Lowder (August 1993). “Novel Ideas”. In Roger E. Moore ed. Dragon #196 (TSR, Inc.), p. 65.
- Richard Lee Byers (July 2002). Dissolution. (Wizards of the Coast), chap. 5. ISBN 0-7869-2714-3.
- Eric L. Boyd (1997). Powers and Pantheons. (TSR, Inc), p. 129. ISBN 0-7869-0657-X.