I don’t like Superman. He’s stupidly overpowered, but he has one major weakness. Kryptonite. A green crystal that came to Earth from light-years away when the planet Krypton exploded. Sure there are other varieties, but we’ll stick with the green for now, since it’s the one that most people are familiar with, and it’s probably the most abundant.
When any Kryptonian comes into close proximity to the radioactive crystals, they weaken, get sick, and will eventually die.
Knowing this, Kryptonians will typically avoid the stuff like the plague. So it would be pretty hard to just stroll up to Superman and hit him with it.
I mean, batman could probably do it, but I don’t think I have any chance getting near him before he either flys away or melts my face off with eye lasers. The only way to get it close to him is to encase it in lead. Lead blocks the radiation, and prevents Superman from using his x-ray vision to see it. Of course, lead is heavy, so a big lead case wouldn’t exactly be easy to carry into battle. Likewise, it would be difficult to retrieve it from the case before the previously mentioned face melting occurs.
What we need, is a long range method of delivering the kryptonite. What we need, is a kryptonite bullet. This has been done before in the comics and on TV before, but it never really seems to kill him. I’ve seen a few arguments against the kryptonite bullet. One, being that as a crystal, it would probably shatter in the barrel of the gun as it’s being fired. Another problem, is that unlike lead, kryptonite would not deform slightly in the barrel, allowing it to better grip the rifling which causes the bullet to spin, and makes it more accurate. The third, of course, being that a bullet made out of nothing but kryptonite could be possibly felt by superman, who would then use his x-ray vision to see through the non lead gun, then melt said gun with his heat vision just prior to melting my face.
In order for this to work, what you would need is something like a Glaser round. A Glaser Saftey Slug is a hollow bullet, filled with bird shot. When you shoot someone, the bullet pretty much disintegrates upon impact. What we would need to do is replace the bird shot with kryptonite, and instead of putting a polymer tip on them, we just close them off with lead. Next, we need a few hired thugs. Someone that Superman won’t expect to be any threat. We arm them with these special bullets, and then send them out into Metropolis to cause trouble in areas that Superman is rather fond of.
Once Superman shows up, he will do the thing that he normally does when confronted by someone with a gun. He’ll stick his chest out, expecting the bullets to simply mush against his indestructible chest. The thugs will then open fire. The first round may not kill him. He will be stunned though, because he will feel it even if it doesn’t introduce enough kryptonite to his system. Yes, he may survive the first shot, but the next dozen or so? Let’s say I use Desert Eagles to arm my thugs. The .50AE rounds would allow for plenty of Kryptonite to be inserted into each round. Each thug would have eight shots with a standard mag, with four thugs, that’s twenty-four shots before they reload, by that time, there will be enough of the green stuff in him to keep him from fighting back. The thugs can then reload and continue to fire at him.
The best part of this method, is that even if he manages to get away, there will be tons of little kryptonite pellets and shards inside him, poisoning him until he dies.