The Nameless City. 2, The stone heart / Faith Erin Hicks ; color by Jordie Bellaire.

Kaidu and Rat have only just recovered from the assassination attempt on the General of All Blades when more chaos breaks loose in the Nameless City: deep conflicts within the Dao nation are making it impossible to find a political solution for the disputed territory of the City itself. To complicate things further, Kaidu is fairly certain he's stumbled on a formula for the lost weapon of the mysterious founders of the City. . . . But sharing it with the Dao military would be a complete betrayal of his friendship with Rat. Can Kai find the right solution before the Dao find themselves at war?.