10 DC Characters Weaker Than Superman Who Could (In Theory) Kill Him

10. Kryptonite Man

Let's get the obvious one out of the way first... "Superman's weakness is Kryptonite... therefore let's make a villain for him who emits Kryptonite radiation!" It's such a lame, boring concept. Several villains have shared this moniker, but for this point we'll be focusing on K. Russell Abernathy. K. Russell Abernathy was a scientist who was on the verge of something big.

Whilst he was working out of a research laboratory on the Avenue of Tomorrow in Metropolis, he developed a Kryptonite isotope enhancer, which would enable Abernathy to harness Kryptonite radiation and convert it into energy. Unfortunately for him, the isotope enhancer overloaded, which caused a massive explosion of Kryptonite radiation in his laboratory.

Not protected by lead shielding, Abernathy took the full brunt of the blast. However, instead of killing him, the massive blast of green radiation mutated him into a living Kryptonite Man. As mad scientists tend to do in such a situation, he immediately went on rampage through the city, firing blasts of green energy from his eyes, causing Superman to intervene (but, obviously, he struggled thanks to the fact that he found the culprit to be made of his weakness).

That said, given that he only gained a slight increase in strength and endurance, his durability, speed and strength aren't even close to Superman's level - and nor does he possess the ability to fly or the power output of Superman's heat vision. However, given that he can fire energy blasts made up of Superman's inherent weakness, he could - theoretically - kill the man of steel given enough time, by completely bombarding him with such blasts.