both would be pretty simple, more so than a lot of other things.
the collar could be made of a strip of cardboard painted silver/black with the screen painted on.....
aluminum foil sounds way dinky.....so not likely there.
you could maybe find a silver headband to wear around your neck, that would look less low budget.
the mase/maize/mace i duno how to spell that, just a rubber ball, or styrofoam, except that doesn't spraypaint well/at all. those spikes are tiny, toothpicks would almost work, or sticks sharpened in a pencil sharpener. attach it to a chain........
would you carry a weapon for battle royale?
Oh, I never thought of the silver headband... I think I saw some, nah I don't think I'm gonna carry a weapon for battle royale, I just want to be a generic student haha, thanks for your help!