Iomedae smites the graveknight so that fighting it will take less of her attention and she can also think.

It could be a trap, obviously. Ehersior likely doesn't know Trace Teleport exists, but Ehersior would have anticipated his people being scried, and might've chosen to make it look like the scryable place they were Teleporting out of was more vulnerable than it really was...

On the other hand. Ehersior wouldn't be expected to be basing his offsite command in Kronquist, because he and Malyas hate each other; Ehersior's one of the Ustalav old guard who were embarrassed in their allegiance to Tar-Baphon when Tar-Baphon declared Malyas ruler of all the vampires. And Ehersior wouldn't be expected to be basing it in Urgir, because they're pretty sure Saravega has the command there presently and he and Ehersior hate each other because - she doesn't even know why. All of Tar-Baphon's eighth circle liches seem to hate each other. Sucks to be the bad guys. 

And the offsite command wouldn't be in Gallowspire because magic is twisted around the place, and scries don't work properly in or out. A powerful spellcaster can get around it, but if you want a nice civilized surveillance setup - and Ehersior would, he's the kind of lich who regards himself as civilized rather than the kind who regards himself as an ancient grasping Urgathoan hungry thing -

You spurn your rivals and set up your own offsite command, Forbiddanced, probably deep underground in some crumbling Ustalavic castle, with a Teleport Trap in the one necessary place it's not Forbiddanced, permitting outward travel with a password and inwards travel not at all. You make sure your strike teams don't themselves know the location, so a Dominate can't betray you. 

She kills the graveknight and catches the armor on the tip of her sword and slides it in one motion into her bag of holding so they can later lay the man to rest. Take us to Arazni, she tells Mathriel. 

Arazni's in a Magnificent Mansion near the front, keeping an eye on things through six different live scries, waiting for Tar-Baphon to show himself or something else to require her attention. This would be a vulnerability - someone could just dispel or disjoin the mansion, and then she'd be in a known location unprepared - but there's a simple fix to that: they have a wizard in an antimagic field standing in front of the entrance to the mansion, suppressing it. If Tar-Baphon drops a disjunction on that location, nothing will happen. 

Iomedae and Mathriel land just outside the antimagic field. Iomedae takes her helmet off and steps into it so they can verify it's her. "Let us in," she says, and the wizard steps briefly aside, and the two of them enter. 

There's a dozen people in the room with Arazni. Mathriel's trick here is a secret. "I need the room," she says, and they start filing out. 

Arazni looks away from her half-dozen scries, trying to parse off Iomedae's face if it's good news or bad. That isn't secret, and it's good for morale for people to see them confident; Iomedae lets herself smile slightly. "I think you're hurting Ehorsior's feelings," she says brightly. "He's gone to all this effort and it hasn't gotten you out of your seat. I bet he fondly remembers the old days when he was enough trouble to drag you onto the field."

        "Well, he misremembers them, if he remembers them fondly," says Arazni, matching Iomedae in her joking tone but with the glittering intensity in her eyes that says she is playing along precisely as long as it takes for everyone else to clear the room and no longer.

"Perhaps he had an advisor who reminded him how badly those fights went, so he killed that advisor, and now is surrounded only by people who assure him they went very well," says Iomedae. "I really suspect it's something like that, sometimes, or else undeath just makes some people incapable of learning from their mistakes." The door swings shut behind the people she ordered out, and she drops the joking tone. "One of your scrolls of Discern Location. Mathriel caught a look at some faces in what might be their offsite command."

       Arazni hands it over. "Are they not in Urgir."

"Didn't look like it," says Mathriel. "...aaaaaand no, they are not. Ehersior's operations base, Sclerain Swamp, Canterwall."

"We have a Trap the Soul gem for Ehersior, don't we," says Iomedae. "He's not on the field yet."

          "- let's do it," says Arazni. "Both of you leave a moment, I have secret preparations. Get me Narthoc and Cassidi unless Restran is available in the next three moments -"

"He's not," says Iomedae. He'd be useful for this, obviously, but he's on the front and will take more than three moments to pull out. They step into the next room and call Narthoc and Cassidi over and return to Arazni, her secret preparations done. 

Arazni's Mind Blanked all the time. There's no guessing what the secret preparations were. She casts Arazni's Haste on all of them, confirms that Mathriel and Narthoc have the relevant spells prepared and recalled even though they always do, and then bends the world around her and changes the rules of magic, like only a god can do.

Maximized Mythic Time Stop. 

Plane Shift, as a spell-like ability posssessed by an astral deva; quickened Teleport, to right on top of the location they just pried out of the enemy; Disintegrate, to cut through the walls. Disjunction.

They survey the room full of motionless undead, looking for anything dangerous, anything unexpected, any traps they've triggered which the Disjunction didn't obviate.

Narthoc pulls an altar to Aroden out of a bag and casts Consecrate.

        Arazni starts putting up maximized empowered Delayed Blast Fireballs. They'll go off after the Trap the Soul, because they don't want to turn Ehersior to ash, here. "Thoughts on who to grab when I split the spell?" she asks. Arazni's single-target spells can hit two people, if she wants them to. They may as well also try trapping someone else's soul; why not?

"Kheves," says Iomedae instantly. She has murdered him eight times and would be delighted not to need a ninth. She's actually confused Arazni asked; he seems like an obviously better secondary target than anyone else in the room, unless she's failing to recognize someone or some feature of the situation -

"- but if we kill him we get that headband," says Mathriel, a bit longingly. "If we soul-trap him we don't."

Iomedae takes a second look at him. The headband looks like a perfectly ordinary good intelligence headband to her. Arazni also looks torn, though, so it must be a really good headband. They have about five more seconds. 

Iomedae takes off her Ring of Protection, puts on a Ring of Evasion. "Get Kheves," she says, "and I'll cut the headband off his head for you first."

       "What, and then we raise you?" says Mathriel, looking at the four maximized empowered delayed blast fireballs now hovering in midair. Arazni's Fireballs bypass fire resistance and fire immunity and hit as hard as Wail of the Banshee when they're not empowered. 

Iomedae is not going to say 'I'll be fine" just as the Time Stop expires. That's tempting fate. 

Soul trapping liches is conventionally considered fairly difficult. Ehersior is very good at throwing off spells. And the gems are expensive; it's not something you can just try repeatedly until it succeeds. The Consecrate will help, a little. The Disjunction will help a lot. But if you want it to be a sure thing -

The Time Stop expires. Iomedae cuts Ehersior's cloak off his shoulders in one stroke. Arazni casts Greater Bestow Curse, targeting a person's ability to resist spells, on both Ehersior and Kheves, and bends the laws of the universe to insist that it affect them, whether it would have or not. Across the room her rapier slaughters the person she judged most likely to successfully dodge the Fireballs. Mathriel casts Greater Bestow Curse also, targeting Ehersior's Wisdom. Cassidi does an Archon's Trumpet, his specialty; he is wildly better at it than actual literal trumpet archons. The Shining Crusade is wearing earplugs. Almost everyone else'll be paralyzed. Narthoc stands there waiting to counterspell anyone who manages to try anything. He's usually bored, when they do raids like these, because usually no one is in any position to try anything. Iomedae slices the headband off Kheves's head, and then gets his cloak too for good measure. Arazni casts her Trap the Soul, and bends the laws of the universe to insist this one work too. It does, on both of them. 

The four maximized empowered delayed blast fireballs go off. It's not a sure thing that Iomedae can dodge Arazni's ninth circle spells, not such a sure thing it seemed like a good idea to tell Mathriel not to worry, but it's awfully close to a sure thing, and in fact she's fine. She looks around for anyone else who survived that. There's a quick-moving wisp of some kind which seems to have managed but Arazni's rapier is now doing cleanup. 

Arazni puts up another mythic Time Stop.

"Tell me if there's anything I shouldn't touch," Iomedae says, and starts sweeping magic items into a bag of holding. If they look like they'll take too long to get off a fried corpse she just hauls the whole corpse in. 

"Right there," says Arazni, pointing, and so that magic item gets special treatment, picked up telekinetically by Mathriel. and dropped into a separate bag. "And right there." 

They Plane Shift back to the mansion, ten seconds after they left. 

And then they can celebrate, at least for another ten seconds.

"I think that was the smoothest that has ever gone. I love your new spell, Mathriel, I adore it. I want to drape a banner round its shoulders and offer it a title."

      "Do you need a Heal," says Arazni.

"No," says Iomedae, only very slightly giddy with glee. "Why would I need a Heal? Have you been laboring under the impression that just because you are a god and a bit of a specialist with Fireballs you could hit me with a spell."

      Arazni actually cracks a grin in response, at that. "If I'd thought it through, probably not, but in the moment I was sure I was going to roast you alive. Which would've been worth it, to be clear, for that headband."

"All right, what in the world is this headband. It looked perfectly normal to me."

       "I think it's stronger than a greater headband," Mathriel says. "I've never seen anything like it before."

"All right, all right, I suppose it's worth roasting me alive for that. If you could, which you can't. - we have a decapitated army out there to go clean up. You'll have to tell me the rest of what we got later."

       "Need any help with it?" says Arazni. 

"Wait and see if Tar-Baphon shows, but I doubt he will, it wouldn't salvage this."

      "Are we chasing them all the way to Vaishali Pass," says Cassidi.

"If we do that, Tar-Baphon probably will show. ..which is to say, yes, absolutely, but let's time that fight for dawn, when Arazni's fresh -"

      "And when I've had time to confirm that the excessively good headband's safe to wear," says Arazni. 

"I will try not to rout the enemy too fast."