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This article or section contains lore taken from the Warcraft RPG books.

A language known by the half-orc skeletal mage, Chauch-eta. Little is known about this language.^{MoM 147}

Perhaps a version of Common or Low Common for the creatures dwelling beneath the earth.

Speculation

This article or section includes speculation, observations or opinions possibly supported by lore or by Blizzard officials. It should not be taken as representing official lore!

"Undercommon" has an apparent connection to DnD derived generic languages, which apparently can be found in DnD rule books. It is the language of the drow, the dark elves.^[1]

References

1. ^ http://www.d20srd.org/srd/skills/speakLanguage.htm