Radigan Conagher, is one of the supporting characters of Team Fortress 2 and Engineer's grandfather. He is a well known wise old man who constructs and fixes machines.
In Loose Canon
Radigan appears in the webcomic Loose Canon. In 1850, he visits a woman named Elizabeth, who convinces him to not build the machine for Blutarch Mann to outlive his "twin" brother Redmond Mann. She offers him australium for an alternative. She also asks him to build a machine for Redmond Mann. Later in Loose Canon page reveal he gains more muscle and becomes Australian-Texan hybrid due to Australium poisoning,turning into Texan version of Saxton Hale.