All The Vampire Formula books 1 to 4 in a boxset ready to binge read on KindleUnlimited. 
Bullied and broken, Jon Harper is given one chance to fight back—with a formula that turns him into something more than human. But every power has its price… 
The Vampire Formula Series – Reading Order:-  The Birth of Vengeance - Book 1The Truth of Vengeance - Book 2The Enemies of Vengeance - Book 3The War of Vengeance - Book 4
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