Boy Thunder's origin revealed in Batman/Superman: World's Finest #7 preview

gamesradar.com:

Batman/Superman: World's Finest focuses on a time when Dick Grayson, the original Robin, was still serving as Batman's sidekick. And in September 20's World's Finest #7, readers will meet the 'Boy Thunder,' Superman's secret sidekick from his early superheroing days.

(By the way, the name 'Boy Thunder' is pretty clearly a play on Robin's nickname 'Boy Wonder.')

Now, a preview of Batman/Superman: World's Finest #7 shows off some of what else readers of the issue can expect, including a reference to the '90s DC concept of 'Hypertime,' in a story that theoretically would have taken place before the concept was introduced in DC continuity.

Here's the preview of the interior pages:

For those who didn't read DC's Kingdom Come sequel The Kingdom which introduced the idea, Hypertime is a concept that states that the DC Universe has numerous branching possible futures, all diverging from specific points in time. 

Hypertime exists in addition to the DC Omniverse and was employed at a time when the concept of a Multiverse of different realities was off the table at DC. In the current DC era, all concepts, stories, and characters from all the different worlds and realities of every DC comic ever published are considered to exist somewhere in the Omniverse, an all-encompassing model for DC's cosmology.

Boy Thunder's identity is seemingly revealed in the preview, though the saga of Superman's secret sidekick will reverberate through World's Finest at least until December's Batman/Superman: World's Finest #10, which will deal with some of the fallout of the young superhero's secrets (while also including a variant cover that features a real-world celebrity whose likeness has been censored till release).

Batman/Superman: World's Finest