Ultimate Worthless Attacks

I was thinking recently about weapons or attacks that are supposed to be really dangerous and yet never actually accomplish anything. I think this started because I've been watching the vast quantity of DragonBall Z clips on Youtube, and my favorite character happens to suffer from this affliction.

See, Krillin (or however you want to spell it) has this attack, the Destructo Disc (hey I didn't name it), which looks like an energy buzz saw that he throws at people that, in theory, will cut right through them. This is potentially a great boon to him, as every enemy the good guys encounter is a lot stronger and faster than he is, and most of the battles are about who's stronger or faster, or who can make the biggest explosions, and the answer is never "Krillin". Unlike his best friend Goku, Krillin isn't an alien whose power increases dramatically any time he gets angry*, so you can see how it would be helpful to have an attack that could offset his other limitations compared to his opponents.

The only problem is, it never works**. They dodge it, they catch it, they are somehow tough enough it doesn't actually work on them***. Or it does work, but they're of a jello-like consistency, so they just sort of melt back together after it cuts them in half. Very frustrating. I suppose part of the problem (besides the obvious issue that he's basically a sidekick/comic relief and so is never allowed to triumph on his own) is it's really an attack best used with the element of surprise, and that's not usually how folks play it in that universe. There have been a few times where I've seen him catch someone completely off guard with a kick to the head, they had no idea he was there, and thought "That would've been a good place to throw the Disc, Krillin." They'd never see it coming, so they couldn't dodge it, and since these guys were weak enough he can hurt them by kicking, then the Disc would definitely have cut them in half. Good times.

I've been trying to think if there's a similar situation in American superhero comics, and the closest I can recall is Darkseid's Omega Effect. It's supposed to be this awesome, one hit kill attack, that once aimed at a target, never misses and yet, Superman isn't dead, because for some reason Darkseid doesn't use it on him. Or doesn't use it on him with intent to kill (I can't buy for a second that by now Darkseid doesn't know exactly how tough Superman is and so he's just not using a strong enough Omega Effect). I suppose it's useful for trashing various flunkies that displease him, but it's not as if Darkseid would need the Omega Effect for that.

Can you think of any other attacks or powers that are supposed to be a big deal, but never really live up to it?

*Actually, Goku's oldest kid is a much worse offender, and it's quite irritating because his power never seems to go up until after one of his friends has died or been badly beaten. Day late, dollar short much, kid?

** Except for once, when he cut off the bad guy's tail. Which served to get said bad guy's attention long enough for the healer they'd befriended to get some of the others up and running again. Eventually, the bad guy transformed to a more powerful state and the tail was whole once more, so in the long run it didn't accomplish much.

***That was bullcrap. They just wanted to save the "Surprise! Cell can regenerate!" for when Vegeta nearly blew up the planet trying to kill Cell, and only succeeded in blowing off his arm.