Possibly using a passed out drunk guy. You soak his balls in tuna fish for about 20 minutes, then you proceed to lay him in a hammock on his stomach with a precise cutout for his nutsack. Then you wait for the neighborhood cats to arrive.
you take a leather sack with a hole in the bottom and hang it from a tree in your backyard. then you climb into the sack after coating your balls in tuna oil. once you're in the sack and your nuts are hanging through the hole, a cage full of angry, hungry cats are let loose in the yard and they rip your balls to shreds.
"Have you seen Drew today?" "No, not since the tuna pinata, he's been in the hospital recovering."