"Is it doable to get more information from the Fade?"

"Not quickly," Solas says, "and not reliably, not in the way you seek."

"If it gives semi-random answers, I can derive a pattern eventually - but you're right that that kind of investigation is time consuming."

And they're starting to get close enough to the Breach to be planning their assault. There's a crater in the center that the ruins slope down to. The Breach is directly above the center of it, far up in the sky. This close, it becomes clear that it is, simply, enormous. Too large for her to close in one go, conceivably. Below, at ground level, is a rift, strangely crystalized, rather than the shimmering rent of all the previous ones she's seen.

"Did it close itself off somehow?"

"It is not truly closed," Solas says, examining it. "It is more akin to a jam of ice in a snowpack river. The flow is halted, but pressure builds up behind."

"Would you recommend reinforcing it, or just lancing and draining?"

"To drain it would be the better course. Left alone, I am sure it would eventually explode, compounding the damage. If you are able to seal it, however... This rift would have been the first. Closing it may at least mitigate the Breach."

"That'll mean reopening it first."

"The Mark should be capable of that, I believe."

"So we'll time it for when we're most ready, then?"

"As best we can. It will break eventually if left to its own devices."

She can set up barriers for any ranged fighters to take cover behind, assorted traps immediately around the rift...

Leliana starts organizing the soldiers with the help of a blond man with a scar on his upper lip, and giving quick briefings. Magical backlog means there could be a shockwave, make sure to take cover. It also might mean powerful demons, given everything else about the past few days. Rage demons, terror demons, maybe even a pride demon. Take cues from Cullen (the blond), Cassandra, and any other templars- let them take the brunt of magical attacks, that's what their training was for.

She coordinates preemptively rearranging the battlefield with Leliana's directions, then...

They're ready.

She'll have to get close to open the rift. Cassandra will guard her.

She appreciates it. 

(Bellona also preemptively arms herself with alchemically-made daggers and a spear, all richly engraved with dragons and hidden arrays.)

And then she's close enough to reach out and pull the rift open. At first it sticks like a rusted door, but then all at once the resistance disappears and it flares into life once more.

Also flaring into existence is a rather large demon, slate grey and spiky, at least twelve feet tall and about that broad across the shoulders. It chuckles ominously as it brandishes a whip made of crackling lightning.

Big demon means big target! And, also, demon standing on the ground means demon in reach. 

What does it feel about the ground turning into a cloud of dust under it - just before the cloud explodes, of course.

It does not appear to be a fan, judging from the enraged bellow.

It does something, pulls energy from the rift somehow, that causes the rift to start crystallizing again. The soldiers' followup attacks on the demon don't have any perceptible effect after it does this.

...Hm, one solution would be reopening the rift, but...

How easy would it be to get her hands on the demon?

Fairly difficult. It seems to be covered in a sort of lightning cloak now, in addition to the quite vigorous way it defends its personal space with the swinging of its arms.

...Okay, ripping the rift back open it is. 

That hurts it! And seems to leave it in a bit of daze, where the soldiers can attack safely without getting walloped themselves.

Which means she can get closer - can hopefully get in close enough to transmute it -