Warning! Spoilers ahead for Superman #31!
In Superman #31, Superboy showed off a new power that even Superman can't pull off. At this point, it's commonly known that Superman is one of the strongest and most advanced superheroes in all of DC Comics. However, this issue proves that even the Man of Steel can be impressed. This issue implies that the range of powers and tricks that Kryptonians can currently do is just the beginning. As they evolve, new abilities can surface just like the power that Superboy showcased.
The Shadowbreed, one of Superman's oldest enemies, has returned to face off against Superman and Superboy. They had suspected that something greater was afoot, but Clark and Jonathan Kent never expected the extent to which the Shadowbreed had returned. Taking over Faldr, an old friend of Superman, they reveal that they have evolved and can take over living organisms. Unbeknownst to Superman and his son, the entire Thakkramite civilization has been turned. Facing only a fraction of their newly-born army, both heroes are forced to retreat as they realize the power that their foe has.
In Superman #31 by Phillip Kennedy Johnson, Scott Godlewski, Norm Rapmund, and Gabe Eltaeb, Superboy shows off a new skill during this initial encounter with the Shadowbreed. After flying away, it's revealed that the power on display was Superboy detonating his heat vision in midair. Clark asks Jonathan about this creative new use of their powers, as he's never seen anything like it. Superman is thoroughly impressed by his son, who explains that he had been playing around with it for a while. Detonating his heat vision works in a way that it reacts with the water molecules in the air as he focuses on bringing the beams together.
Superboy's actions, once again, prove that he is becoming worthy of the Superman mantle. This continues the current path that they are leading Jonathan down, especially with Superman: Son of Kal-El taking over very soon. Literally and fictionally, Superboy is being pushed to take up the mantle. Although it's inferred that Superman cannot use this power, there's a possibility that he can. It could be interpreted that Superman had just never thought of it and therefore. There's a chance that Superman might try to learn this new ability and he may use it in future comics.
Ultimately, what's clear is that Superman is being set up to pass on the cape to his son. It's likely that in Superman: Son of Kal-El, Superboy will take that next step and his father will step back. Currently, Superboy has another chance to impress Superman as he is the only person left standing. With the Thakkramites infected and Superman taken over, Jonathan is his father's last hope of survival.