Reign (Deluxe Edition) by Bethan Croome

The Kingdom of Lyonesse is absent of magic but not of rain.

In the rain-soaked Kingdom of Lyonesse, magic is outlawed―punishable by death.

So when Niamh's forbidden witchcraft is exposed, she flees her rainy village disguised as a man.

She never meant to end up on a battlefield.

Mistakenly conscripted into a brutal war engineered by a paranoid king against a vengeful sorceress determined to reclaim the throne, Niamh now hides another secret―her womanhood. Between fighting terrifying beasts and confronting arcane powers she once believed were merely folklore, Niamh is thrust into a world where survival relies on more than luck―it demands alliances.

In battle, Niamh must obey Prince Fitzroy, the king's infuriatingly handsome illegitimate son and sharp-tongued commander tasked with eradicating magic. He is everything she despises…and everything she struggles to resist. Back at camp, she forges a complicated friendship with Bash, a fellow soldier who sees her like no one else does and stirs forbidden feelings that could shatter her disguise.

As war tightens its grip on the kingdom, Niamh is forced to choose: obey the prince who could expose her, trust the soldier who could love her, or embrace the forbidden magic that could save them all.

But war is merciless, and not everyone will live to see which side prevails.