Agreed, this should be an MvM reward for a halloween tour only.

I myself would rather have valve readd old spells back into the drop system via tour rewards, but I doubt they'd be willing to do so, so this could be a replacement for it (most people don't like botkillers so I doubt they'd like this either)

I'd replace the barbed wire with a noose. It would fit way more, especially the zombie head ones.
I don't like the zombie head (and the eyeball one for knife) design, but it could be improved by making the eyes dark pits with black goo oozing out from them.

With that said, I still wouldn't want this added into the game (because who wants more botkillers?), but I'd rather have it be a botkiller like reward for completing a mission rather than a festivizer like tool that would allow you to put it on any appliable weapon.

this is really cool and would be a cool Halloween unlock.

I want this, but I also would like to see someone make this for the regular robot heads to be a chance of dropping in Mann vs Machine to apply to any weapon, as well as these for halloween.