Bearik Hammerstone

Armed with a great maul fashioned of black ice and girded in plate mail made of the same stuff, Baerick Hammerstone is the leader of a group of xenophobic dwarves who have severed ties with Stokely Silverstream and brought the dwarven valley to the brink of civil war.
Until recently, he was merely a simple stone carver living peaceably with his fellow dwarves. Several months ago, Baerick’s fortunes changed when he joined a small expedition formed by a wizard’s apprentice from Luskan. The group began near the summit of Kelvin’s Cairn, where Baerick helped to unearth the undead form of Akar Kessell, the long-dead Tyrant of Icewind Dale. Under Kessell’s leadership, the expedition journeyed to the northern slopes of the Spine of the World. After much searching, Baerick found what the undead wizard sought: a black stone as smooth as glass. Though it seemed translucent at first glance, a trick of the eye caused it to look darker the longer Baerick squinted at it, as if the stone were drinking in light. More impressively, when he took his pick to the stone, he could not damage it.
While Akar Kessell dithered about what to do with the substance, another miner tried to seize the stone, and Baerick buried his pick in the other dwarf ’s skull. The rest of the miners set upon him and one another in a mad scramble to acquire the strange stone, until only Baerick survived—much to Kessell’s amusement. With the wizard’s help, Baerick gathered as much of the black ice as the wizard’s magic could help him carry and returned to Kelvin’s Cairn.
Back at his workshop, Baerick set about trying to carve the stone. He discovered that heating the stone in a forge softened it enough to be carved, and he began fashioning small trinkets from the samples he had brought back. Baerick put his “black ice” trinkets, as he dubbed them, up for sale, and they spread quickly among the dwarves. With Kessell’s help and encouragement, Baerick excavated more of the black ice and sold his trinkets even more widely. The wizard apprentice who first hired him acted as his agent in Ten-Towns, and soon Baerick received commissions for other objects made of black ice—knives, fishing hooks, even a ram for one of the boats on Lac Dinneshere. Eventually, he began to experiment with fashioning weapons and armor from the black ice.
What Baerick did not realize was that the black stone was ice-infused with the remnants of the Cryshal-Tirith erected by Akar Kessell over a century ago. Forged from the essence of the evil Crystal Shard, the Cryshal-Tirith carried a trace of the shard’s taint, and thus so does the black ice formed from its remnants. The taint slowly corrupts anyone who comes into possession of the black ice, although the effect is more pronounced in those who have more contact with the substance.

(Information from the Sundering Adventure Legacy of the Crystal Shard and stats are adapted from those provided for D&D Next.)