These Shattered Spires by Cassidy Ellis Salter — book slip

In a world decaying beneath a tooth-filled sky, the arcanists of Fourspires Castle face a deadly competition to crown a new ruler after the king's assassination.

The arcanists, each from one of the four disciplines—blood, bone, stone, and botany—must battle to the top of the Fifth Tower. For the familiars, who serve as both servants and sources of power, this competition means certain death.

Nixie, a botanical familiar, discovers a way to avoid this fate by finding four cursed keys with familiars from each discipline.

With only forty-eight hours before the competition begins, these unlikely allies must decide if they can trust each other long enough to save themselves.

Perfect for fans of Leigh Bardugo and Gideon the Ninth.