Faction Paradox/Nightmare Fuel

The Faction Paradox. Let us state what makes these gentlemen worthy of mention, shall we? First of all, they have their roots in corrupt Gallifreyan Expies worshipping paradox and defiling history and glorifying death as the mother of all Take Thats to the Time Lords. They entered existence by paradoxically creating their own creator. Said creator became a monstrous undead paradox being whose shape depends upon who's looking at him. The shape he always uses? A twisted image of the viewer, being "everything you swore you'd never be". In essence, the embodiment of all potential evil in the universe. The Faction as a whole has as a favorite sport for initiates a manhunt in which they are led to their ancestors and Unperson themselves by murdering dear old papa or gramma before they themselves are born, therefore erasing themselves out of history and making them harder to destroy by time-based attacks. They wear masks of pure bone out of the skulls of creatures that never ever existed. They use huge skeletons as warships. They merge weapons with their shadows and turn them into living monstrosities that can slice apart rooms while the priest remains calmly sitting.
A particular member of the Faction mentioned he once murdered his father. Typical. And then went to his timeship and went a few hours earlier. And killed him again. And again. And again.
The Celestis are the former Celestial Intervention Agency agents, who feared that in the War they would be erased from history. So they did it to themselves in their own terms. Now, a moment to think... a lot of members of a society where paranoia and Chronic Backstabbing Disorder is the norm, turned into Energy Beings, who can only remain anchored in reality as long as someone believes in them. The A God Am I scenario, predictably, is the best of all. As a commenter states on their rotting society: nothing can be all right in a society where everybody is either a god, a slave or an assassin.
- They have a biodata virus. Biodata, for comparison, is a sort of 4-dimensional DNA, mapping who you are and how you affect the timeline. Said virus works by latching into your timeline and fucking with your history so you become a servant of Paradox. Before you contract it.
Think the jealous, borderline insane Evil!Brig!TARDIS of Zagreus was monstrous? Pah. Think of an Ax Crazy timeship whose existence has all been pain and madness from its very birth. Give it sentience and a desire to kill and destroy every living thing. Add to that a factory capable of bringing those killed back to life. In a most horrific manner, of course, being integrated painfully, organ by organ. And then raped For the Evulz. Forever and ever. Congrats. You just imagined dear old Antipathy.
And of course. Lolita EATING the Eleven-Day Empire.
The hardened veterans of the War In Heaven are less Humanoid Abominations... and more One Winged Angels...
The Yssgaroth, infinitely horrific monsters from another Universe are related to the Great Vampires of the normal Whoniverse, so you know it's going to get bad. Their taint is easily transmissible and the timeline in their universe is implied to be self-cannibalizing. Turns out, they're grand at the biological scientist thing. How good are they? Good enough to string your nervous system across continents while leaving you fully conscious, incapable of death and of feeling anything other than endless pain. Fate Worse Than Death doesn't begin to describe what will happen if the Yssgaroth get you. Oh, and did we mention there's a good possibility the Yssgaroth are all part of a single, unfathomably huge organism? And the local Time Lord expies have been leading incursions into their universe for military purposes?
Hell, the very premise of the Eleven-Day Empire. An extradimensional realm created by mutilating Earth's history and populating it with Eldritch Abominations by the goddamn truckload. It is protected by entities implied to be the physical embodiments of the Laws of the Universe. And the massive potential for Temporal Paradoxes merely by existing there for any length of time. And then came the news of the War in Heaven...
- Now, for the benefit of the good people around here who don't know what this War in Heaven business possibly could be, let us translate into terms a normal Whovian can understand. You might have (or have not) speculated on how horrible the Last Great Time War could possibly have been for every single participant: Dalek, Time Lord, Eldritch Abomination and beyond. Now, a little experiment: imagine you have access to a time machine. You are engaged in combat with another person who also has a time machine. A wreckage of a Gambit Pileup later, none of you are closer to killing the other as both continually fight to retain your timeline intact even as you try to make Time itself your bitch as you alter time as well as you can with your technology. Now, placed in perspective: imagine it's not two, but trillions of participants in a battle royale for control of the Universe in every moment in time. Now you perhaps understand. And there are people seeking to exploit it! The gall of them! But do not worry, friends. The Faction's door is always open...
Ahoy, gentlemen! Ripped from the headlines - the true Homeworld of the Ene my has been identified - it is none other than Earth!
The Time Lord Invasion of Earth in Dead Romance. Full stop.