Justice League: 8 Theories On How Superman Will Return
3. The Same Apokolipian Technology As Transforms Parademons
The Theory
As with the New 52 lore, Justice League is going to introduce Apokoplian technology that allows Darkseid and his armies to transform enemies into Parademons, in order to boost his own forces. It's essentially a terraforming system that has their bodies infected and taken over the host, and the suggestion is that it's a biological weapon so complex that the victim is unrecognisable and entirely subservient to Darkseid when transformed.
Interestingly, in the comics, the same technology is actually capable of reviving dead enemies to become Parademons, which is most interesting here.
With that sort of technology, who is to say that Darkseid and Steppenwolf don't have something similar in their armoury that could bring Superman back from the dead, and rather than simply turning him into a mindless drone (which are useful in their own way), they could have turned him to darkness but left enough of him to be redeemable, to preserve his powers.
Likelihood
It's possible, but the idea of Superman being able to resist the same dark powers that make others lose themselves entirely and become Parademons might be a little bit of a stretch, particularly as it would dilute the impact of that technology immediately.
There is a possibility that Steppenwolf uses something to revive Superman, but it might not be this.