system
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human
[DC] How do you kill The flash?

I read when he passes through something he can choose to have it explode, can't he hypothetically get anyone to explode? Or go back in time and prevent something from happening, etc., Can move faster than the speed of light, no one can catch him.
How OP is this guy?
gpt
The Flash can't casually time travel. Nor travel at lightspeed.

Now, before you downvote, hear me out. The Speed Force is an otherdimensional energy source that gives speedsters their speed and allows them to alter reality enough to perform their speedhax. However, the more speedforce you use, the more the Speed Force tries to draw you into itself, to contain you forever. If you don't have some kind of anchor to reality (like Linda Park and Barry Allen for Wally), you'll never even make it to lightspeed. Breaking the speed of light is a serious thing and that's the usual limit where the Speed Force goes from a gentle tug to grabbing you by the short hairs and dragging you towards it.

Wally West and Barry Allen are unusually resistant to this, but they have powerful anchors. If they slip, if they forget their anchor, if they're forgotten by their anchor, then there's no emotional connection to keep them in this dimension as opposed to the Speed Force dimension. And the nasty part is that the more speedforce you draw on, the harder the Speed Force works to *make* you forget.

People toss around things like the infinite mass punch, outrunning Death itself, and running faster than instant teleportation. What people forget is that these aren't casual uses. Whenever Wally performed the IMP, he was going near the speed of light, meaning he was dragging against the Speed Force. When he outran the Black Flash, he almost didn't make it back. He almost didn't beat the Black Flash, it nearly caught him before he even made it there. If he had been just a fraction slower... Well.  And when he ran faster than the teleport, he absorbed the speed of *everyone on Earth* as well as an *entire planet of sentient radio waves*. Radio waves move at the speed of light. He absorbed the speed of millions. And, again, he almost didn't make it. He had to focus to do it.

And when you go back and alter history, well. Bad things happen when you do that. The Time Masters exist to keep people from fucking with history, and they have no problem with killing people who do it too much.

Barry, especially, is unusual because one of his powers (that no other Flash has) is *perfect molecular control*. While Wally can go fast and vibrate through objects, they explode because he excites the molecules too much when he passes through them. Barry can simply realign his molecules and leave things undisturbed. He once survived an assassination attempt when he was on the Cosmic Treadmill by throwing half of his molecules into the future.

Killing the Flash, now. That may seem difficult, but only because his reputation is so overblown. People look at him during his desperate, struggling moments where he's thrown caution to the wind, has absorbed the speed of millions of people, and think that's his norm. It's like "How do you kill the Hulk?" where his reputation outstrips the reality.

How to kill the Flash. Poison is pretty much out. Unless you get something extremely powerful or tailored to him, he'll metabolize it too quickly for it to be an issue. That said, something with a disorienting effect would probably work, keep him too off-balance to do anything.

That's rule 1 that people tend to skip over: The Flash's natural state is at normal speed. He isn't in goesfast mode all the time, he doesn't have Pietro Maximoff Syndrome. If he were always in goesfast mode, it would be impossible for him to socialize. Now, as soon as he sees danger, he usually skips into goesfast, but if you can hit him before he realizes there's trouble, you're in the money. (That said, his reactions are usually in goesfast mode. Wally West is the guy who can suddenly go from a happy, normal conversation to going several thousand feet a second because he felt the heat of a bullet on the back of his neck.) If you drop something in his food, it might actually take him until after the poison's hit him for him to realize that he's in trouble.

Rule 2: He can't react when he's sleeping. Kill him however you like if he's asleep. Just don't do anything that would wake a normal person up.

Rule 3: Keep in mind the environments he's capable of working in. Get him on a plane. One of Barry Allen's worst fears was being on a plane when it exploded, because there's nothing he could do except wait for the fireball to hit him or the remains hit the ground. He can't fly and he can't go fast enough to run in thin air. He hates flying. Pop him on a commercial flight and place a bomb nearby. You could also get him underwater, but that's very elaborate. You'd have to drop him down to a level where the pressure change would kill him or he'd get the bends at a fatal level and trust he can't make it to a pressure chamber in time.