Baldur's Gate : The Sword Coast Chronicles : NWN2 Persistent World

Using the Taunt Feat:

It seems that a ROLL of 20 on the save is an auto save regardless if the it beats the DC.

Saving Throws are supposed to auto-succeed on a roll of 20.

Per the description of Taunt, it is your skill roll VS the defender's Will save. skill roll's won't auto succeed or fail, but will saves can auto-succeed.