Decade of Death

Every decade, 6 children are ripped from their beds at the Dead of night.No one knows when or who will be taken. Just that its going to happen.
The date changes every year and so do the categories. Each child is given a single category and made to choose an animal from their designated category and made to fight to the death in the Decreation
The reasoning? Population control set by the government after the population get to high that they cant sustain people.
No one knows anything about the Decreation except that they will will watch 5 of their beloved children aged 4-16 be brutally slaughtered by one another.
But what happens when an outcast ,hated by society, gets taken? Will she find a flaw or will she perish?