Liberation of Rynn's World

The Liberation of Rynn's World was one of the first recorded campaigns conducted by the newly created Ultima Founding Space Marine Paladins of Thunder, who were comprised entirely of newly revealed Primaris Space Marines. This campaign was a part of the much larger, galaxy-spanning Indomitus Crusade undertaken by the military forces of the Imperium of Man and led by the resurrected Ultramarines Primarch Roboute Guilliman, the new acting Lord Commander of the Imperium. When the Chapter homeworld of the Crimson Fists were besieged by both a large greenskin invasion and then a large invasion by the Forces of Chaos, the forces of the Paladins of Thunder Chapter answered the call. It was during this notable conflict that the powerful bond between the Crimson Fists and the Paladins of Thunder began, even before the tragic death of the Paladins' first Magister Medicae (Chapter Master) fell to the enemy's blade.

History
They accompanied the other Primaris Space Marines during the Indomitus Crusade and, maybe because of their gene-seed made them do it or because of the situation of the planet, the Paladins of Thunder fought alongside the surviving Crimson Fists and their Primaris reinforcements on Rynn's World; killing foul daemons of chaos and saving both human and astartes lives. During this part of the crusade, Magister Medicae Talassar died saving a Lieutenant and a couple of Crimson Fists marines from the blow of a daemon of Khorne, as he used both his narthecium and his plasma pistol to break the gargantuan axe; as his iron halo broke during a previous fight. Due to his sacrifice, Pedro Kantor, once the battle was over, promised the new leader of the chapter; Aemilius Castor, that the Crimson Fists will be with their brothers in their time of need as well as they did.