The story is called Valkyrie Commander.
Sienna Murphy has been a tactician for quite some time. She never knows where the Rite of Tol will take her next.
One day, the Rite of Tol takes her and Collin to a universe where technology is crafted into weapons to defeat the Honkai. At first, Sienna just wants to go home, but if she wants to leave, she will have to defeat the Honkai and save the technological universe
