Kardan Stronos
Kardan Stronos is an Iron Farther of the Iron Hands and the closest thing they have to a Chapter Master. He's role is closer to that of the US President or UK Prime Minster than the normal Chapter Master.
What little we know of him is that he's about 90% machine however that doesn't seem to be his brain as he's smart enough to realized the point a group ruling is that they don't all have the same ideals, which isn't something you get with all Iron Fathers. As such he's been adding other ranking members into Clan Council over the years, and been encouraging more healthy ways to deal with their emotions than just repressing them. This also worries a lot of the Iron Fathers, as Stronos doesn't have a very good track record in mastering his own emotions. During one campaign he was challenged by a World Eaters champion of Khorne to single combat. Although calculating that the simplest way to defeat him was by shooting him in the head, in the end he charged the Champion while screaming at the top his lungs in a blind rage before decapitating him. May not be the most expedient method, but it gets shit done. He also has a massive boner for Razorbacks, believing firepower is the only major tenet of combat and wants to outfit the entire Chapter with Razorbacks.
While his penchant for dealing with Khornates is effective, the enemy of the Imperium of Man Stronos hates more than any other are the Necrons, viewing the soulless automatons as abominations in the eyes of the Omnissiah. Which also makes him a whole lot smarter than most Techpriests, who tend to start bowing down and worshiping the Necrons right as they're powering up the Gauss weapons. When expecting to face Necrons he takes more forces than the Clan Council believes is necessary, not stopping until every Necron in sight is destroyed or teleported off the field.