Lazarus
Lazarus is the current Master of the Dark Angels Chapter's 5th Company and is their contribution to the initiative of making new characters that cross the Rubicon Primaris. He appeared in the September 2019 issue of White Dwarf before he got his full rules in Psychic Awakening: Ritual of the Damned.
Lazarus was a sergeant by the time Magnus the Red decided to nuke some yiffs. He won some renown here by helping lead the counter-attack when the forces of Chaos tried to storm The Rock. At some point after the Circatrix Maledictum ripped the galaxy a new goatse hole open, the 5th company's captain, Balthasar of Dark Vengeance fame, had fallen in battle and Lazarus was elected to take his place.
He swore vengeance for this insult and got his chance shortly after when Magnus tried to conquer the Stygius Sector. This went mega-terribly as the sorcerers all went mindfucky on him. His injuries proved so serious that his only chance of survival was to become a newer, better breed of Space Marine. This would mark the first time a Primarine entered the Inner Circle, though it was handwaved by the fact that he was already in the organization beforehand.
Crunch
While he looks familiar, acting as a Primaris Captain with all the rules involved, this is where his wargear steps in to differentiate him. His sword is the Emnity's Edge, which is a dangerous S+2 AP-4 D1d3 that can re-roll to wound and the damage rolls when fighting an enemy psyker. He also has the Spiritshield Helm, which houses a special force field to all models within 6" that can potentially negate mortal wounds. His last special rule is Intractable Will, which lets him make some final attacks in melee in the event that he goes down.