Son of Mischief, Magic, and Metal

What started as a mission to get Loki's sceptor back, turns into a rescue mission when they find a little boy powering the whole damn base.
And when they find out he's disables, a trained killer, only seven, and looks almost exactly like Loki, shit gets personal.
Over the years, they raise an incredibly child who goes through all sorts of hell.
Then, he turns eleven and gets sent to a badass boarding school in Scottland where it only gets crazyier.
Did I mention he's a wizard?