Spike awakens within the Realm of Ninjago after being sucked into the Crystal Mirror after it's been behaving strangely, as a result after he and the Mane 6 investigate it, he is sucked into the Mirror upon hearing a strange voice, and the Mirror is broken which prevents him from coming back in any known way.
Spike awakens on the doorsteps of an old Monastery and is found by a man named Master Wu, who takes him in and lets him join a team of Ninja who all have cool Elemental powers, despite not having any powers.. yet, he's trained as a ninja to unlock his own potential and find his calling. And now Spike's life is being a part of a team who can be a new family with him, and hopefully he can find a way home one day..