or "grasshoppers" & "Judo heads" (with the wire arms that grab the grass)
If he used any of those he was an idiot. If you're trying to deter the animal use a rubber bludgeon head, 
which will sting an awful lot if you don't hit it in the vitals or head. Although with an animal the size of a cat it would be hard not to hit those areas. Any of those other ones are going to cause big damage and you won't get a passthrough on anything bigger than a blackbird.
I'm thinking a paintball gun would also do a wonderful job of deterring marauding cats and dogs and only end up stinging and getting them a little funny colored. Too bad someone hasn't come up with clear paintballs yet. I think that would be a million dollar idea!