Earth Logic takes place a few years after Fire Logic. Karis’ odd little family is doing its best to stay together and support her while raising their daughter. (Technically, Norina’s biological daughter, but everyone is raising her. Considering how extremely hyperactive the kid is, they might be outnumbered.)
What they are also trying to do is find a way to deal with the problem inherent in trying to defuse a threat without continuing the war being fought because of the threat. (A recurring theme in Marks’ work is war in and of itself being a problem, instead of a solution to the problem. Do not go into a Marks fantasy expecting the “war is bad but sometimes necessary” trope you will not find it, and only become dreadfully confused and disappointed as a result.) A new addition to the family is a cook named Garland, a Sainnite deserter. He runs into Karis, and ends up cooking meals for the entire family, even though he suspects they are kind of crazy. (It doesn’t help that most of them agree with him.)
The tactics of Karis and her family are strange and chaotic. Because of dreams and portents, they conclude that in order to deal with the Sainnites, Zanja will have to die, and Medric will have to write a book. (Thanks to Norina, Zanja does not literally die, only metaphorically, which causes some interesting problems later on.) The book Medric writes is essentially a pamphlet explaining a little bit about how Sainnites–who call themselves “Carolins” think, and why the Sainnites are kind of doomed. Karis meanwhile, learns about her mother’s people, and works to stop a plague that the Sainnites accidentally brought with them. (She also spends a great deal of time being Extremely Unhappy with Zanja being metaphorically dead.)
While Karis and friends contemplate the problem of the Sainnites, a Sainnite lieutenant general named Clement is wishing she were not contemplating how far up crap creek her people have paddled. Thanks to the constant warfare between the Shaftali and the Sainnites, her people are facing a very slow very ugly death because they are not able to replace their numbers. (Sainnites do not really have families as such, most children are raised in a children’s garrison. Both men and women are soldiers, but female soldiers are forbidden to bear children. Since they are in extremely hostile, conquered territory–and no back up since they were driven out of their home country–they have no real infrastructure.) Despite being aware of how much trouble her people are in, she cannot really do anything about it because her immediate superior, the general of all the Sainnites, is a total idiot.
Clement’s situation becomes further complicated when an attack on her garrison leads to her having the not so brilliant idea of kidnapping Shaftali kids as recruits for the army. This draws the attention of an organization of fanatical Shaftali calling themselves “Death and Life.” (This organization is also the reason why Mabin decides to apologize and work with Karis. Death and Life do not follow the traditions Mabin upholds, and they break her air-logic brain.) Subsequent adventures involving a mysterious story teller, an informant who would like his daughter back, please, and a Shaftali cow doctor lead her to adopting a child and deciding that she would really like the war to end.
Earth Logic is a great story. Marks has a talent for taking the standard fantasy tropes and then pretty much ignoring them. (Which is definitely a good thing.)