This would be part of a "magic" act where every trick apparently goes wrong with horrific results. Severed limbs, bodies actually cut in half, blood and gore throughout, each stunt ending with the player standing and taking a bow while wiping off the fake blood. Pen and Teller did a stunt with a fake
stabbing of a hand which was great, this show would expand on that.
The William Tell part would have a can with a collapsible arrow made out of a spring that pops out of the can and sticks to the player's forehead after another collapsable arrow in the bow across the stage disappears into the bow appearing to have been shot.
The idea here, just to be clear is just the fake arrow through the head trick.
ADDENDUM: Here's a way you could do this with off the shelf stuff:
1- Foam arrow with a flesh colored suction cup at the end. Standard thing kids used to play with but with a very shock absorbing end.
2- Printed tissue fake arrowhead that covers the suction cup and collapses when the arrow hits the forehead.
So the archer can show the audience it's a "real" arrowhead which disappears when it hits the guy with the can, apple, whatever on his head.
And since Penn and Teller's knife through the hand is the greatest magic trick ever, there really should be a complete show with nothing but fake disasters based on that. Dark comedy magic show? I'd want to see it.
But again, that's not the idea. It's the arrow thing.
Or you could have a rubber suction cup that's turned inside out to form a fake arrowhead. When it hits the target it collapses and TURNS INTO a suction cup.
Okay, I'm putting too much thought into this. Moving on.