"I Am Unstoppable!"

Acquisition
Skill Quests
 * Cold As Ice (Sif Shadowhunter in Sifhalla)

Trivia

 * The phrase is often said by Juggernaut from Marvel comics, especially in the Marvel vs. Capcom 2 arcade game.
 * The Unreal Tournament series often refers to a player as "Unstoppable" when killing 12 or more players in a row.