Nightwatch on the Hinterlands
(Book)

"The war that ripped the multiverse: Generations ago, a massive war tore a hole in the multiverse. Now extraplanar monsters surge out of the Weep at irregular intervals along its jagged border, held back by an alliance of templars and arithmancers, soldiers and priests. The Templar: When Lieutenant Iari hears screams in the night, she expects to interrupt a robbery or break up a fight. Instead, she discovers a murder with an impossible suspect: a Riev, one of the battle-mecha decommissioned after the end of the last surge, repurposed for manual labor. Riev don't kill people. And yet, clearly, one has. Iari sets out to find it. The Spy: Officially, Gaer is an ambassador from the vakari Five Tribes. Unofficially, he's also a spy, sending information back to his government about the Weep, unfiltered by diplomatic channels. Unlike Iari, Gaer isn't so sure the Riev's behavior is just a malfunction. The Riev were created using a mixture of alchemy and arithmancy. It can't be a coincidence that here, along the edge of the Weep, the Riev are also acting in unexplained, and increasingly dangerous, ways. As Iari and Gaer search for truth, they discover that the murderous Riev is just a weapon in the hands of a wielder with wider ambitions than homicide, who is willing to release horrors not seen since the war-horrors that make rampaging riev seem insignificant."