The guardians of law and purity, these wage an unceasing battle against the demons. They are severe in their judgement and will rarely spare a mutant , as they are touched by chaos. However they are overwhelmed by the extent of the devastation and may have to prioritise their targets if potential allies include mutants. They will try to induct newly transformed seraphs into their way of thinking as well as providing them with protection. The planes of pure law are far rarer than those of chaos but Seraphs are examplars of physical and spiritual prowess. They appear as tall (6'-8'), muscled, perfectly proportioned human men or women, with large feathered wings extending from their shoulder blades.
MR Range 100 - 1000 Special Features - Flight - Large feathered wings Pure Voice - the voice of a seraph is beautiful to behold and can be understood by any creature with a language. Special attacks Voice of Pure reason - The seraph can present a formidable argument. IQ or Cha SR at L2 required or the target will stop and consider their words to the exclusion of all other matters until the paradox is resolved. Broken if the target is attacked. 1/Sword of Light - the blades wielded by Seraphs do triple spite damage to any mutant or demon.
Note transformed player characters do not have the above powers , but do have the physique , compelling voice and functioning wings.
When an unprotected being is engulfed in the planar collision they must make a L3 Luck saving roll. If they fail the roll they take 2d6 Con damage, + 1 for every point they were short. If they survive this damage it will heal in the normal way. They then roll for the effects of the transformation on the appropriate tables.
1) Have the Cataclysm affect an existing campaign. The portals start to appear. IQ SR or Talent history/arcane lore check of L4 to have an inkling into what is going on. Anyone who puts their arm into a portal must make a L1 Luck SR or take the difference in damage. If they fumble (roll3) they lose their arm and take 3d6 damage. If they roll a L5 or higher SR their arm is placed with a functionally improved one (bonus strength or claws or similar). People talk about the end of days, and powerful wizards start selecting those they will protect with Pentagrams. PC's have a choice, endure the transformation, or seek protection, then face the invading hordes.
2) A new campaign - the Transformed. The PC's are all mutants who survived the transformation. Maybe they knew each other first, maybe they did not. They are all disoriented, suffering loss of loved ones, and shunned by the fragments of civilisation (at first at least). Then demons start arriving , trying to enslave them, recruit them or kill them.
3) A new campaign - the Guild of Light - a powerful wizard managed to protect his/her friends, family and household - the adventurers are amongst those that were saved. They must then venture into the demon blasted wilds, to see what can be salvaged, to make new alliances, and to prevent the invasion.