I suppose eventually he would've ran out of his teammates' descendants...

Somebody on Twitter posted this issue's cover, and I didn't recall having seen it before, even as part of Legends of the Dead Earth! From 1996, Legion of Super-Heroes Annual #7, "One Shot" Co-plotted and scripted by Tom Peyer, co-plotted and colored by Tom McCraw, pencils by Mike Collins, inks by Mark Farmer and Robin Riggs. Cover by Alan Davis!

Legion stories traditionally took place in the 30th century, but we're up to the 75th today; as Wildfire passes out rings to the newest Legionnaires, as they're about to face off against an alien threat he had faced multiple times before--failing every time! The aliens were destroying stars every century or so, which would be bad enough, but seemed secondary to their main goal: isolating the former worlds of the United Planets. This batch of Legionnaires doesn't have the team spirit of the classic team: xenophobic and distrustful, they all seem to suspect each other of being allied with the alien foe, and get disintegrated pretty quickly. Wildfire's containment suit is destroyed, but his energy and the flight rings are gathered by the oddball brain-jellyfish member, Membrain.

In a new containment suit, Wildfire is distraught, not over losing his teammates, but for dooming the galaxy to another century of distrust and isolationism. Membrain had noticed something, when Wildfire was briefly blinded and deafened, and suggests a sensory-deprivation experiment for Wildfire to try and recall some of the memories he had lost over the centuries. Like his real name, Drake Burroughs, or the accident that turned him into energy. The next spot has to almost be torture, remembering the good days with the Legion, and his fondness for Jenni, the speedster XS. But it gives him an idea, and starting with Durla, he begins recruiting pairs of teenagers: Durlan shape-shifters, Braalian magnetics, Carggite triplicators, and winged Reniians. He went with pairs, telling them it's in case one dies he has a spare; but along with his training also tells them there's no fraternizing allowed. None! None of that! Yeah, because telling teenagers not to do something is a deterrent, at all...

After the rookie team stops a whalelike alien from stealing Rimbor's oceans (which felt like a callback to something, like an old Weird War Stories maybe?) the shadowy aliens behind the sun-destroyer decide to move up their timetable, and take out Rimbor's sun now. Wildfire is forced to play the cards he has: he had planned a longer game, with their grandkids; since he knew by telling them not to he guaranteed they absolutely would...No spoilers for the rest, but longtime Legion readers might guess the culprits. Now if I could find Legionnaires Annual #3, which appears to be mostly an XS solo story.