Ancient Stone is an epic tier feat available to goliath characters level 21 or above.
Normally, an epic tier goliath can use the stone's endurance racial power to gain resist 15 to all damage, and the effect ends at the end of the character's next turn. The Ancient Stone feat partially extends that effect. When the stone's endurance effect ends for a character with the Ancient Stone feat, the character gains resist 10 to all damage until the end of the character's next turn after stone's endurance ended.[PH2:194]