Phobia
“With great fear comes great power”
A phenomena where children with phobias gain powers related to their greatest fear making the children unstable and destructive when their fear is stimulated.
Ex. hydrophobia = water bending (A child with this caused a tsunami that killed millions including her/him.)
You are a 13 year old child with sciophobia (fear of shadows), this fear caused the death of your parents when you were 9 and ever since then your home became a research facility on an island where the government puts children like you.
There are only ten of you there because only a small population of children are affected, and that some die before the government got to them.
All ten of you undergo test where you have to face your fears head on with the hope that you can overcome the fear and be able to use your power safely.
The government has some shady motive though since they are planning to use you as tools to gain dominion over other nations.