ARENA IDEA!
There's no cornucopia, all the supplies are hidden underground in bunkers, the arena is slow and quiet, tons of water and stuff to hunt for the first few days until the bombs drop which turn it into a hellish place
There's a random countdown constantly in the sky so some tributes hide underground, most either die due to the bomb, radiation sickness or the nuclear mutts who basically poison you if they come near
The bunkers are small underground but there's lots of them (about 5), there's a radiation suit in one
One night, all the light in the bunkers turn off n the mutts are let in, they look like your family with extreme radiation sickness, begging you to help them.....
If they get bitten or touched, they have 3 days to live but this sickness makes you blood hungry before all the other symptoms kick in....
And since your locked in with them it doesn't turn out well....
Games last: 2 weeks
Based on d13 kinda