So he explains the war, from the start, with digressions to tell the history of Arda. He elides politics as irrelevant. He tries to make guesses about the current capabilities of the Enemy but their intelligence is mostly out of date. 

Lazarus pays attention, because he might be useful to this enterprise, they might need him to past-watch more magic for strategic purposes. But he was not kidding around when he said he was very upset. He's being quiet about it, but he is in fact very, very upset.

Which is kind of soothing, really. It is nice to know there's a shocked and appalled multiverse out there. When he gets to the present he says "...so, any questions?"

"Do you anticipate interference from the Valar if I evacuate Angband and then obliterate Melkor? Would the evacuees of Angband likely do anything unfortunate with their sudden freedom?"

"The Valar wouldn't interfere with that. I have no idea how many of the Enemy's lieutenants would continue doing evil if evacuated but it's certainly some of them. Even if orcs weren't bound to serve Melkor at this point there's also four hundred years of wars with Elves as reason they have to hate us. There might also be infighting, not sure. The prisoners might be some of them rigged by the Enemy to snap and kill everyone around them, that's something that happens." 

"The standard solution for this sort of thing on worlds that are being actively ruled by Bells who are openly deploying magic is a generic prohibition on nonconsensual violence applied uniformly to the entire world. Would this be likely provocative?"

"That sounds fantastic."

"Okay, so no design challenges, just a ground rule, evacuating Angband, and obliterating the Enemy. Jane, I need Stella."

"You rang?"

"Three wishes. Does your sorter work if you don't even know what they're for?"

"...Apparently," says Stella, clinking coins into Angela's hand. "But I can't tell you which is which."

"I'll figure it out."

"Pen mentioned wishes."

"They're our most flexibly applicable form of magic. They come in sizes and one of Stella's aura powers" (Stella kisses Lazarus on the forehead, then vanishes) "can determine in advance how big a coin is needed for a task, so I don't have to step up gradually and guess. Looks like this doesn't even need a tenner. Would one of you hold the door for me, please?"

They do.

And Angela pokes her head into Arda and makes three wishes.

"There you go."

"That's - it? Angband's evacuated, the Enemy's dead, and there's no nonconsensual violence anywhere in the world?"

"Yes. I suppose the evacuees might not be in a maximally convenient place, but I found somewhere with room for all of them and nobody else in the immediate vicinity."

"Where? We can send food and supplies and so forth - and the people who do oath-scrubbing could see what that does for orcs..."

She brainphones him a picture of the area and a zoomed out aerial view. "I'm sure Keziah and Céleste will be happy to come back and de-oath more people but it may also be doable with wishes, and if it is it'll be more efficient that way, this is a pretty big population and there are only the two of them."

"Okay, yes, we can send food and supplies there. If wishes aren't a limited commodity then that'll be far more efficient, there are nearly a million orcs."

"They're slightly limited, they just batch well - if I can de-oath with a hex I can probably de-oath thousands with a star and cover the entire orc population with an evil."

"Fantastic. And some people might panic if they run into orcs and find themselves unable to draw weapons on them but no one will actually die and I'm getting the word out as swiftly as I can, the King's already told his people."

"People can brandish weapons all they like, it's less constraining than that."

"What does it prevent? If it doesn't prevent talking people into suicide I know one of the Enemy's lieutenants who was really excellent at that..."