Image by the author using Midjourney.
Malcolm Gerardus was a captain of the Imperial Army that served at the Battle of Viterbo, where he lost the lower half of his left leg. He said that he met Solarian at Viterbo.
Captain Gerardus has recently discovered he has Solari gifts. He can rapidly grow his fingernails, and change their form to another material (such as wood, or gold). However, the fingernails disappear when removed.