Secret Histories feats (For Heaven's Eyes Only)

Upon being stabbed at the end of Book 4, Eddie's spirit went to Limbo. Once he's brought back to life, Molly explains some of Limbo's workings to him:

“I will agree to change the subject,” I said. “But only because I’m still waiting to hear what happened to me after I was stabbed!”

“Your spirit went to Limbo,” said Molly. “You weren’t, properly speaking, alive, but I’d seen to it that death couldn’t claim you. So Limbo took you until my magics could supercharge the healing process and repair your body enough for your spirit to return. You were in . . . spiritual shock. Neither in one condition nor the other. Limbo isn’t a place, as such. When you go there, your mind creates its own setting. It’s perfectly possible”—and here she broke off to scowl at Roger for a moment—“that all the people you saw there were really only parts of your own mind, talking to one another. Working out old issues and unresolved conflicts. Psychotherapy for the soul.” -For Heaven's Eyes Only, Chapter 2: No Place Like Home

Molly turns a dozen people into toads at once:

“Buy me some time, Molly,” I said.
Molly stepped forward to stand beside me, snapped her fingers sharply and the Satanists closest to us suddenly disappeared, replaced by a dozen very surprised-looking toads. Really ugly, warty toads. The next-nearest Satanists fell back, ducking into doorways to give themselves cover.

Isabella sniffed loudly. “Toads. I thought you’d outgrown that, Molly.” -For Heaven's Eyes Only, Chapter 3: Hell Hath Fury

Molly and Isabella proceed to beat the living shit out of several people, drawing blood and breaking bones with their strikes:

I expected them to smite the Satanists hip and thigh with destructive spells and really messy magics, but instead Molly and Isabella strode down the corridor side by side, walked straight through the dead dog as though they were ghosts and then threw themselves at the nearest Satanists. Basically, the witches beat the shit out of the poor sods, their small fists flying with appalling speed and precision. Blood flew, bones broke and the air was full of horrid sounds as the Metcalf sisters knocked the Satanists down with much malice aforethought and trampled them underfoot. The Satanists had braced themselves for a magical attack, but two fistfighting young witches were a bit too close and personal. Molly and Isabella pressed forward, laughing harshly in the face of the demoralised enemy.

Behind my golden mask I had to grin. Never get a Metcalf sister mad at you. -For Heaven's Eyes Only, Chapter 3: Hell Hath Fury

Both Molly and Isabella are capable of turning bullets into flowers after they're fired, even doing so to close-range automatic gunfire:

Some of the Satanists remembered they had guns, and opened fire again. Molly and Isabella stood their ground, whipping their hands back and forth in mystical patterns, and bullets turned into flowers and fluttered to the floor. Some Satanists ditched their handguns for automatic weapons, but it didn’t make any difference. Just meant more flowers. -For Heaven's Eyes Only, Chapter 3: Hell Hath Fury

The Metcalf sisters can summon flames hot enough to incinerate people into nothing but ash:

The two witches leaned over the stairwell, chanted something in unison and extended their hands. Great waves of fire burst from their fingertips, gushing blasts of hot yellow flames that shot down the shaft and incinerated the dead bodies coming up. Fire filled the shaft, so hot the air rippled around it and the stairwell walls blackened. There was a brief stench of burnt meat, and then even that was gone. The flames snapped off. The air still shimmered with heat haze, and I had to wait a few moments before I could take a look. All the dead men and women were gone. Nothing left behind to mark their presence but some scorch marks on the steps below, and a few ashes floating on the air.

“Fire purifies,” said Molly. “If you do it right.” -For Heaven's Eyes Only, Chapter 3: Hell Hath Fury

Ethel can "see into dimensions you don't have names for yet", yet she/it can't see into William Drood's mind properly:

I looked up into the rose red glow that marked Ethel’s presence. “I had hoped springing him from that asylum and bringing him home to the family might help him.”

“Sorry, Eddie,” said Ethel, her calm and kind voice seeming to come from everywhere at once. “I’m doing all I can to soothe his troubled brow, but someone has done a real number on this man’s mind. I can barely see into his head, and I can see into dimensions you don’t even have names for yet. Trying to sort through his thoughts is like drowning in a bucket of boiling cats. There’s a lot going on inside his mind, but it’s all going on at the same time. It’s a wonder to me he can even see the real world. He is fighting it, Eddie; but I think he’s losing. And . . .”

“Yes?” I said, after the pause had gone on a little too long for my liking.

“There’re . . . other things in his head, too,” Ethel said reluctantly. “Shadows . . . things I can’t even identify. I’ve no idea what they are.” -For Heaven's Eyes Only, Chapter Four: Too Many Secrets for One Family

First mention of Ammonia Vom Acht:

“If we have to hire someone,” I said carefully, “I say we hire the best. And that means Ammonia Vom Acht.”

Everyone reacted, and none of them favourably. The Armourer pulled a sour face, and the Sarjeant shook his head firmly. Harry and Roger looked at each other, and neither of them looked pleased by the prospect. William was back to staring off into space again. I looked at Molly, and she made a point of being very interested in the remaining contents of her bag of popcorn.

“All right,” I said. “Agreed, she’s a poisonous, vicious and really quite appalling woman, and those are her good points. But you know you’re going to get your money’s worth with her.”

“I should hope so,” said the Sarjeant. “Given how much she charges.”

“How do you know how much she charges?” I said.

“I have made my own overtures,” said the Sarjeant. “Once it became clear that we were going to have to do something about William.”

“I’m still here!” said William.

“Only just,” said the Sarjeant. “But can we really risk allowing that woman into Drood Hall? She could rip the secrets out of everyone’s head in ten seconds flat.” -For Heaven's Eyes Only, Chapter Four: Too Many Secrets for One Family

Molly can erect protections that can prevent people from listening in on her. Apparently, she thinks even the goddess Gaea can't hear past them:

“Molly, I need you to put up all your best privacy spells right now. I need protections so strong that no one will be able to overhear what I have to tell you. Do it now.”

“Who are you worried will listen in?” said Molly, as she stepped back and struck a series of mystical poses, her hands moving so quickly they left shimmering trails on the air.

“Everyone.”

“Including your own family?”

“Especially them.”

Molly made a final gesture and the whole room shuddered. The floor seemed to drop away an inch or so beneath my feet, and then steadied. There was a faint but very real tension on the air. Molly nodded briskly.

“Done and done. You can talk freely, Eddie. Gaea herself couldn’t overhear us now. What’s so important?” -For Heaven's Eyes Only, Chapter Four: Too Many Secrets for One Family

The language Enochian, first spoken of in the Nightside series, gets another mention here:

“See this one, dearie? The shimmering sphere with the bloodred flaw? That is the original Scrying Stone that Dr. Dee used to learn the artificial language Enochian, created expressly so that men could talk directly with angels. If you could only reestablish contact with the same spirit that spoke with Dr. Dee, who knows what secrets you might learn?” -For Heaven's Eyes Only

The Oblivion Brothers are apparently affiliated with the Droods:

“Never trust an elf, or anything they leave behind. You can bet most of it’s boody-trapped, ready to do something transformative and allegedly humorous to whatever poor fool picks it up without industrial-strength gloves on.”
“They’ve got a wand,” I said. “It looks very nice.”
“Traps are supposed to look inviting. Elf wands are just the sugar coating on the trap, because they’re one of the few elven weapons a human could actually use.”
“I know a private investigator in the Nightside who uses one,” I said. “Larry Oblivion.”
“Yes, but he’s dead!” said Molly. “There’s not a lot more the wand can do to him! Hey, how is it you know someone from the Nightside? I thought Droods weren’t allowed in the Nightside.”
“We have agreed not to enter,” I said. “There’s a difference. We could go in if we wanted to; we choose not to. Wouldn’t be seen dead in the place, myself. I know Larry because he and his brothers did some work for the family recently.”
“Rather you than me,” said Molly. “That Hadleigh Oblivion gives me the creeps.” -For Heaven's Eyes Only

Remember those description theory bombs mentioned in the second Nightside book? Well, this is a good explanation for how they would work:

At the next booth, a scientist in the traditional white coat was demonstrating description theory with a blackboard and a piece of chalk, to an only mildly interested crowd. He didn’t seem to have anything to sell, but he was so earnest and determined that people were willing to listen. They watched, frowning, as he stalked back and forth before his blackboard; like so many dogs being shown a card trick, they could sense something clever was happening, but couldn’t follow it.
Basically, the scientist explained, description theory says that if you can describe something exactly, using mathematics, then the maths is the object, and vice versa. So if you change the maths, you change the object. His theory had many applications when it comes to weapons: Description theory bombs, where the maths can persuade a city it isn’t there anymore. Or even transportation, where the maths can persuade the universe that people are where the maths says they are. -For Heaven's Eyes Only

Molly turns a barrage of automatic gunfire into butterflies:

A man with an automatic rifle stepped out from a booth opposite and opened fire on her. I didn’t even have time to react. Molly stuck out one hand, and the bullets turned into butterflies in midair long before they reached her. Pretty pink butterflies, like animated scraps of sugar floss. -For Heaven's Eyes Only

Molly is implied to need psychic protection to deal with Ammonia Vom Acht:

“I’ve got something for you, Molly,” the Armourer said quickly. “Come and take a look at this little beauty.”
He scrabbled among the assorted tech and junk cluttering up his worktable, tossed aside a pistol with five barrels and a fluffy gonk with an evil stare, and finally held up a golden crown: a simple circle of gold, with an intricate golden lattice containing dozens of brightly shimmering crystals. He offered the crown to Molly, and she looked it over while being very careful not to touch it. The Armourer preened proudly.
“Very nice,” Molly said finally. “Expensive, but vulgar, vaguely Celtic in design, but aesthetically pleasing from every angle. What am I supposed to do with it?”
“You put it on your head!” said the Armourer. “It’ll protect you from every known form of psychic attack, and make damn sure Ammonia Vom Acht can’t prise any useful secrets out of your pretty little head.” -For Heaven's Eyes Only

Molly stuck her lower lip out and looked at me. “Why doesn’t he have to wear one?”
“Because I have a torc,” I said patiently. “And psychic protection comes standard. Please put the crown on, Molly, or I’ll have to go without you. You go up against Ammonia Vom Acht with an unprotected mind and she’ll rip your thoughts open and gut them like a fish, with one look.” -For Heaven's Eyes Only

Ammonia is stated to be the most powerful human telepath in the world today:

“Ammonia won’t think I’m . . . scared of her, will she, wearing protective headgear in her presence?”
“It won’t even occur to her that you wouldn’t be scared,” said the Armourer. “Anyone with half a working brain in her head would have enough sense to be scared shitless of Ammonia Vom Acht. The most powerful telepathic mind in the world today . . . Well, human mind, anyway. If you were to enter her presence unprotected, even for a moment, she could read every thought you ever had, or make you think you were someone else and always had been, or plant secret hidden commands for future behaviour so deep in your subconscious even other telepaths wouldn’t know they were there. Until it was far too late. Or, even worse . . . she might think of something funny to do to you. Ammonia’s sense of humour isn’t what you’d call normal.” -For Heaven's Eyes Only

Some of the stories about Ammonia Vom Acht:

“Some of her more famous cases, then,” I said. “Just the high points. She was once asked to help resolve a case of split personality in a very important and well-connected person, where the two personalities were in conflict with each other. The dominant good guy versus the usually subordinate trickster type. Ammonia decided she liked the trickster personality better, so she made that the dominant personality and put the other one to sleep. Lot of trouble there, until he was finally removed from office with a lead ballot. Another time, she was hired to investigate an amnesiac, only to discover he’d already paid a substantial amount to a previous telepath to wipe all his memories, because he couldn’t stand being the kind of man he’d become. Ammonia agreed, destroyed his memories again, only even more thoroughly, kept all the money the man’s family had paid her, and defied them to do anything about it!”
“So far, I have no problem with any of this,” said Molly.
“You wouldn’t,” I said. But it gets worse. Having decided that she now knew better than anyone else what was good for people, Ammonia then went through a phase of overhauling the personalities of everyone she met. Rewriting their minds for the better . . . according to her lights. More like telepathic muggings. Some of these rewritings were successful; others weren’t. A lot of people ended up killing themselves, because they knew they weren’t who they were supposed to be. Some of them killed other people, because some subtle restraint had been removed. But by then Ammonia had moved on, never around to clean up the messes she’d made. She stopped only because practically every other telepath in the world got together and ganged up on her and made her stop. Such a gathering was made possible only through my family’s intervention, and I’m not sure we could make it happen a second time. Getting telepaths to work together is like herding cats. It is possible, but only with the continued threat of immediate extreme violence. Which can be very wearing . . . I’m pretty sure Ammonia still blames us for stopping her fun. Anyway, after all this she went into a bit of a sulk and retreated from the world. Only comes out to work on cases no one else can manage; and then only for the challenge, and a truly massive fee.
“She lives all the way out here because she knows too many secrets. No one can keep anything from her, you see. And since she’s met pretty much everyone who matters, at one time or another, there are always agents and assassins on her trail, either to kidnap her to force those secrets out of her, or to kill her to make sure her secrets die with her. She could hide herself so completely that no one could find her, but her pride won’t allow that. And she does so love to prove she’s still as powerful as everyone’s afraid she is. So she stays here, and lets her enemies get close enough that she can have some fun playing with them. Sometimes she lets them get right to her gate before she makes their heads explode. Sometimes she mind-wipes them, and leaves them to wander the world as horrific living examples. And sometimes she rewrites them and sends them back to murder the people who sent them to kill her.”
“Okay,” said Molly. “You’ve said your piece. I feel very thoroughly lectured and warned. Do you feel better?”
“Not really, no.” -For Heaven's Eyes Only

When she was born, she had to develop her own psychic shield to keep herself from hearing the thoughts of the entire world. Also, she can pick up psychic traces and echoes from things like used furniture and long-term meat products:

“Do you know the story? It’s not one of the better-known ones, but it is jolly interesting. Ammonia spent the first ten years of her life in a coma, you see. Self-inflicted, to protect her developing mind from the thoughts of all the world crashing in on her at once. She had to learn how to make a shield that would keep everyone else out, before she could decide on who she was. Think of the poor child knowing all there was to know about human nature at such a young and defenceless age. The good and the bad, the sane and the insane, the saints and the devils . . . Only an iron will kept her together. . . . That’s what makes her such a marvellous curative telepath. She knows all there is to know about the demons of the mind, because she’s been there. You’re very good at what you do, aren’t you, dear? Yes, you are.”
“Peter . . .” said Ammonia.
“I’m telling them what they need to know, old thing.” Peter smiled conspiratorially at Molly and me. “I see you’ve noticed all the fittings and furnishings are terribly up-to-date. Have to be. Ammonia can pick up traces, echoes, from all the people who used to own old things. People imprint on everything, you see. She had to run a full-scale telepathic exorcism on the cottage before we could move in, wiping the stone tape recording clean, as it were. And all the furniture has to be replaced regularly, every twelve months, because they soak up memories. We hold a nice little bonfire for the old stuff, out back. Because you can never tell what another telepath might pick up from it. For a telepath like Ammonia, peace of mind is everything. Everything. Isn’t that right, old girl?”
“Yes,” said Ammonia.
“And she has to be a vegetarian,” said Peter. “Because she can hear the dying screams and last terrified emotions of even the smallest piece of meat. Someone once told me that a plant screams when it’s plucked from the ground, but apparently that’s not true. Certainly not root vegetables, because we eat enough of the things. I haven’t had a sausage in years. Can’t even pig out when she’s away. You always know, don’t you, dear?” -For Heaven's Eyes Only

...And apparently Molly's new crown and Eddie's Torc are enough to keep her out of their heads:

“Does she always let you do all the talking?” said Molly.
“Mostly,” said Peter, entirely unperturbed. “It’s what I’m for. She has no small talk, poor old thing. And she doesn’t trust anyone. All the time we’ve been sitting here, chatting so cosily, she’s been trying to break through your shields, to see if she can. It’s not that she wants to know things; she can’t help herself. Have I distracted them enough now, old dear? Jolly good . . . I’ll be quiet. Got some serious liver damage to be getting on with. . . .” -For Heaven's Eyes Only

Molly erects a forcefield upon entering a strange new environment:

I looked around for Molly and found she was standing right beside me, but now floating quite happily in midair. She stood on nothing, defying the uncertain ground, surrounded by a shimmering field of unnatural forces. She looked down at me and I nodded briefly. -For Heaven's Eyes Only

Molly's forcefield maintains Earth-normal conditions within its boundaries, preventing her from being affected by any strange conditions present outside of it:

I looked up at her. “Are you okay inside that spangly bubble of yours?”
“This is a spiritual force shield,” Molly said firmly. “I am maintaining Earth-normal conditions around me by sheer effort of will. Anyone else would have the sense to be impressed.”
“Sorry,” I said. “I don’t do impressed.”
“I know. It’s one of your better qualities.” -For Heaven's Eyes Only

Isabelle Drood has a hell of a lot of powerful and important people she can get information from, including John Taylor, the Lord of Thorns, Ash from Shadows Fall, and Razor Eddie, among others:

“Iz has contacts on every side of the fence,” Molly said proudly. “She knows people in places most people don’t even want to admit exist. They tell her things. If they know what’s good for them.”
“People . . .” I said dubiously. “What kind of people are we talking about here? I’m not going to place much trust in information that comes from anonymous sources. And neither will my family. I need names, Isabella.”
She sighed loudly, in a put-upon kind of way. “Oh, very well, if you’re going to be stuffy about it . . . John Taylor, from the Nightside. Razor Eddie, punk god of the straight razor. A ghost called Ash, from Shadows Fall. Jimmy Thunder, god for hire. The Grey Eidolon, the Lord of Thorns, and the Regent of Shadows.” -For Heaven's Eyes Only

Molly brushes aside some avoidance spells:

Molly and I wandered around the outer lobby, looking the place over. The old walls looked solid enough, but my torc-backed Sight led me immediately to one particular section tucked away in a corner. As we approached, several quite powerful move along; nothing to see here avoidance spells kicked in, more than enough to divert normal attention. Molly brushed them aside with a sweep of her hand, like clinging cobwebs. -For Heaven's Eyes Only

The satanic conspiracy's sorcerers are capable of redirecting teleportation with prep time:

“Why do you think Roger let you go?” he said, in an infuriatingly reasonable tone of voice. We knew Molly and Isabella were still hanging around, waiting for a chance to jump in and rescue you, so we made that possible. When they teleported you out, we were waiting, and it was a simple task for a few of our more accomplished sorcerers to reach in and grab Isabella and materialise her in one of our places of power. She never even saw it coming. And while she is a very talented young lady, we have some very powerful people of our own these days. People who can tell which way the wind is blowing. -For Heaven's Eyes Only

A major demonic entity appears, and Eddie is unsure of whether or not Drood armour can stand up to it:

We strode down the corridor together, took the sharp left turn, and found it wasn’t a demon dog after all. The whole of the corridor before us had been changed, transformed, possessed by a spirit out of Hell. The corridor was alive, its every surface organic, fleshy, corrupt. Like the living throat that had replaced the elevator shaft back at Lightbringer House. The walls were flesh: scarlet and purple meat, with dark rotting patches and networks of heavy, pulsing veins. The floor was a long, rippling, shocking pink tongue, slick with digestive juices. The whole of the ceiling was one long elongated eye, watching us unblinkingly with mad, fascinated intent. Huge, jagged teeth protruded from the meat of the walls in regular rows; and as we watched, they began to revolve slowly, like a meat grinder, or a living chain saw. The whole thing stank of blood and sulphur and sour milk; it was alive and it was hungry and it was waiting for us. I looked at Harry.
“After you.”
“It’s only meat and teeth,” said Harry. “You really think that could get through our armour?”
“That . . . is a demon out of Hell,” I said. “A major power and a major presence, to be able to overwrite our reality so completely. I have absolutely no idea what that thing could do to our armour.” -For Heaven's Eyes Only

When Harry shoots it full of strange matter bullets, it repairs itself easily:

And then we both broke off and stared blankly as the ripped and torn-up flesh of the possessed corridor repaired itself, rebuilding and reestablishing itself, demonic flesh fusing back together until the corridor looked exactly as it had before. Rotting walls, pulsing tongue, watching eye.
“Damn,” said Harry.
“Well, quite,” I said. “Major demonic presence . . .”
“Now what do we do? Send out for a tanker full of holy water?” -For Heaven's Eyes Only

The Timeless Moment is first mentioned in this novel. The Armourer describes it:

“Sorry, drifting . . . 1943. October. Uncle Laurence was checking out a particularly nasty coven down in Nantes when he stumbled over information about the Satanists’ secret bolt-hole and weapons depository, tucked away in the Timeless Moment. I’m not sure whether the Satanists created the place, or discovered it, or moved in and took it away from someone else. . . . Either way, it was the perfect hiding place. The Satanists established their main headquarters there, where none of their enemies could reach them. All right, Molly, don’t be so impatient; I’m getting there. The Timeless Moment was, and presumably still is, a pocket dimension of a kind, outside time and space as we know them. A strange alternate dimension tucked away between the tick and tock of linear time. Very hard to locate, and even harder to get into. Uncle Laurence led the mission to destroy the dimensional doorway the Satanists used to access the Timeless Moment, cutting the rank and file off from their headquarters, their leader and all the secret superweapons they’d been hoarding there to present to Hitler to help him win the war. Without all this, the rank and file were fatally weakened. Most of them legged it for the nearest horizon and disappeared. The few who stuck it out lost all their influence with Nazi High Command once it became clear they couldn’t deliver all the marvellous things they’d promised. That was the end for them as a vital force in the war. Which helped us win the war, no doubt about it.” -For Heaven's Eyes Only

This is what they see when they travel to the Timeless Moment:

Howard was already moving among his people, talking to them quietly, getting them over the shock and back to work. Display screens everywhere were blank, showing nothing but a shimmering silver void all around the Hall.
“There’s nothing out there,” said one of the technicians, his voice rising. “Nothing! No matter, no energy; that’s not even light as we understand it. This is what the end of the universe will look like, when the game’s finally over and the doors have been shut and the chairs piled up on the tables. . . .”
“Somebody give that man a stiff drink,” said Howard. “And a slap round the head. This is no time to be going to pieces, people. Which part of ‘we are going to a whole different reality’ did you not understand? Now get working; there has to be something out there. Even if it’s only this Castle Horror the Satanists are hiding out in. Come on, people; how can you miss a whole castle?”
The technicians busied themselves at their work, and a certain calm fell across the ops room as they concentrated on familiar tasks. The Sarjeant moved in beside Howard.
“No matter, no energy?” he said quietly. “What about gravity, and heat and . . . things like that? Everything seems normal enough in here.”
“The Hall’s many defences and protections are still running,” said Howard, just as quietly. “I made sure of that before the Armourer activated that bloody machine. I had to be sure we would survive under whatever conditions, or lack of them, we ended up in. The shields preserve our reality inside the Hall. Of course, what happens to us when we go outside . . .”
“Hold everything,” said the no-longer-panicking technician. “New readings coming in. We seem to have stabilised. I’m getting . . . no damage reports from anywhere in the Hall. According to the long-range sensors, conditions outside the Hall are . . . surprisingly Earth normal. Air, gravity, temperature . . . all within acceptable limits. That can’t be a coincidence. I don’t think this place just happened. . . . I think somebody built it.”
“I don’t know whether that’s more or less worrying,” I said.
“Could it be the conspiracy?” said Molly. “The original one, I mean, back in the nineteen forties.”
“No way in hell,” said the technician. “This is far beyond their abilities. Far beyond ours . . . More likely they found it, somehow, and then moved in. And built their castle. This isn’t just a pocket dimension; it’s a whole other reality.”
“Could we survive outside the Hall without our armour?” said the Sarjeant.
“Probably,” said Howard, moving quickly from workstation to workstation, studying display screens over his people’s shoulders. “But I wouldn’t try it. Armour up and stay armoured up until we’re all safely out of here. Ah! Castle, ho! The Hall appears to be calmly floating in this silver void, and roughly half a mile below us is a castle floating in the void! Put it up on the main display screen.” -For Heaven's Eyes Only

The Armourer apparently has a clicker designed to nullify magic:

Alexandre Dusk smiled smugly at me. The bullet wound in his forehead was almost completely healed. He lifted his hands, and dark energies spit and swirled around them.
“I have my power, and I have my shields,” he said. “You can’t kill me, and you can’t stop me.”
“Wrong,” said the Armourer. He raised his clicker, snapped it once, and the magics surrounding Dusk’s hands disappeared. He looked at his hands dumbly for a moment, and then looked back at us. The Armourer smiled. “There are all kinds of clickers. Eddie, would you care to . . . ?” -For Heaven's Eyes Only