Adamantine Splint Mail

Knights of the Red Griffon designed this armor in memory of their fallen leader, Staldrad the Unyielding. When the Great Beast descended upon the Southern Highlands, Staldrad stood his ground as the beast bore down upon him. After the battle, Staldrad's armor was found undamaged, though Staldrad himself was pulverized within.
This suit of armor is reinforced with adamantine. While you're wearing it, any critical hit against you becomes a normal hit.