Lmao, Alloy, are you writing this with "movie" knowledge?
1. Let's think for a second, that Batman Is able to make kryptonite or "get" it ever so illogically from somewhere.
Agreed then Super man won't go near him, what then?
He'll just fry him dude, he has a "LASER" beam (God know fucking how) in his eyes, and if you ask me how he knew batnig had kryptonite, well as you know Kal El can see through anything but lead.
Okay, if you say batman's belt is made of lead (WTF!), we'll Kal El is not immediately affected by kryptonite, once he feels it, he has the time and power to run away unless someone more powerful than Kal El is holding him.
2. Kryptonite is impossible to "make", the comic is set on Earth and nowhere is it mentioned that they live on a different dimension, dude, they are in the Solar System in the Orion arm in the milky way galaxy, that is precisely where we are.
Now comes the question why?
Dude, have a look at the periodic table, the bottom most are the f-block elements, they are highly radioactive!
We've seen that Luthor can hold kryptonite and dance with it and whatnot, that's fucking impossible if it's radioactive and beyond that why don't we have proper names for elements 100 and beyond?, cuz they are of practically no use and created for showbiz except a few, IUPAC has therefore generalized their names with rules.
In conclusion, if kryptonite is created it would obviously come after the 118th element (I think that was the last one) and obviously it would radioactive, so "obviously" Luthor OR Batman can't "keep" it for themselves or be near it, but they do, so Kryptonite ain't radioactive (by contradiction), therefore it can't be made.
@
SmG Battlefire noob, Kryptonians have a higher IQ than home sapiens on average.
Therefore, Kal El wins.