A Blade's Rebirth - D K Holmberg - Bog

When a power greater than the Chain Breaker rips through his realm, Gavin must become more.
When a strange power breaks into Gavin's world from the other realm, he must find a way to stop it-and the ones responsible for forcing open the dangerous vents of power that let terrifying creatures into his world. But too many openings are forming.
Gavin and his allies don't have the numbers.
Worse, when the truth about these openings is revealed, Gavin fears a war unlike the world has seen in ages will return.
And he may be the only thing standing in the way-if he can control his changing power in time.