Silver-Tongued Devil

Silver-Tongued Devil is an achievement earned by winning 50 Speech challenges.

Glitch/Exploit
The following may not work for all versions and all platforms.

Go to Big Town, speak to Bittercup, who usually is sleeping in the Common House. Talk to her until she mentions she dated Pappy. Speak to Pappy. The easy speech check "I heard you came here with Bittercup" dialogue option will never disappear, giving the player a chance to earn unlimited experience and an easy way to earn the achievement. This is no longer possible on the PS3 version as the Pappy exploit has been patched and removed.