Teen Wolf: Hunter's Mark

So, MCs name is Nathaniel lockwood he was born in a hunter family not a very well-known one, but they could live without having a normal job. At 1 year old the hunter's tattoo appeared at his left chest and continue to grow along with him his parents decided they didn't have a choice and start training as soon as he could. At 4 years old his mother died in an accident and his father started his training in the hunter's ways and conditioning while they were traveling around the United States solving cases. At 15 years old he had his first kill and many more followed also he and his father had many fights throughout the years as they couldn't connect and his father in his grief treated him more like a soldier than a son. And now we are at 17 years old seven months after his birthday. I forgot A SMALL LITTLE detail the power of the tattoo will activate at his 18th birthday