With this spell the caster could understand a text that was otherwise incomprehensible to him or her. The caster would see or touch the object or creature with the text in order to cast the spell. Despite being able to read the text the caster would not be able to write or speak the language of the text. The inability to read did not effect the ability to use the spell and learn the meaning of the affected text. Every version of the spell except the first one gave the caster the ability to also understand the spoken words of the language.
The reversed spell, confuse languages, took away the ability to understand normally comprehensible languages from the target for its duration.
According to the Book of the Silver Talon, the ingredients for the ink used to inscribe comprehend languages into spellbooks were: one ounce of giant squid sepia, the fresh tongue of a mammal, the brain of a sentient creature and either one medium onyx or an equivalent amount of sard.
The mineral was crushed into powder and sprinkled over the brain while cooking in a crucible, after which the tongue was inserted whole. Once this combination was burnt into ash, it was stirred in liquid with a duskwood wand and left to sit for 13 hours. Then the powder was added to the sepia and slowly brought to a boil without stirring. Once the vapors of this heated concoction turned from red to black it had to be removed from heat, and stored in an air-tight container.
- ↑ 1.0 1.1 1.2 slade, James Butler (November 1996). Netheril: Empire of Magic (The Winds of Netheril). (TSR, Inc.), pp. 23,27. ISBN 0-7869-0437-2.
- ↑ 2.0 2.1 Mike Mearls, Jeremy Crawford (2014). Player's Handbook 5th edition. (Wizards of the Coast), pp. 207–211,224. ISBN 978-0-7869-6560-1.
- ↑ 3.0 3.1 3.2 3.3 Jonathan Tweet, Monte Cook, Skip Williams (July 2003). Player's Handbook 3.5 edition. (Wizards of the Coast), p. 212. ISBN 0-7869-2886-7.
- ↑ James Wyatt, Darrin Drader, Christopher Perkins (October 2003). Book of Exalted Deeds. (TSR, Inc), p. 87. ISBN 0-7869-3136-1.
- ↑ 5.0 5.1 5.2 5.3 5.4 David "Zeb" Cook (August 1989). Player's Handbook (2nd edition). (TSR, Inc.), p. 133. ISBN 0-88038-716-5.
- ↑ Richard Baker (1996). Player's Option: Spells & Magic. (TSR, Inc), p. 180. ISBN 0-7869-0394-5.
- ↑ Jeff Grubb and Andria Hayday (April 1992). Arabian Adventures. (TSR, Inc), p. 152. ISBN 978-1560763581.
- ↑ slade, James Butler (November 1996). Netheril: Empire of Magic (The Winds of Netheril). (TSR, Inc.), p. 121. ISBN 0-7869-0437-2.
- ↑ 9.0 9.1 9.2 Gary Gygax (1978). Players Handbook 1st edition. (TSR, Inc.), p. 65. ISBN 0-9356-9601-6.
- ↑ 10.0 10.1 10.2 Mike Mearls, Jeremy Crawford (2014). Player's Handbook 5th edition. (Wizards of the Coast), p. 224. ISBN 978-0-7869-6560-1.
- ↑ Mike Mearls, Jeremy Crawford (2014). Player's Handbook 5th edition. (Wizards of the Coast), p. 203. ISBN 978-0-7869-6560-1.
- ↑ James P. Davis (2008). The Shield of Weeping Ghosts. (Wizards of the Coast), p. 116. ISBN 978-0-7869-4877-2.
- ↑ 13.0 13.1 Ed Greenwood, Tim Beach (1995). Pages from the Mages. (TSR, Inc), p. 22. ISBN 0-7869-0183-7.