Clearly the fine folks behind Big Bang (that is, Chris Ecker and Gary Carlson) knew a winner when they saw one, hence the return of the Pantheon of Heroes, whom Dragon briefly met back in #12. Also, the cover is drawn by Dave Cockrum, who was best known for his work on LoSH before that whole "Giant Size X-Men #1" thing. Oh, and if you're wondering, there is a tribute to the Legion's iconic first appearance cover (as well as that other one where the Legion of Super Villains sentences Superman to death)
But that's not actually in the story. No, the story begins just where #14 left off, with Dragon in the Time Being's palace, having discovered a room full of helpless, dying Ultimen being sapped of their powers.
Clone Boy of the Pantheon of Heroes shows himself, explaining that the Time Being was the Pantheon's greatest enemy (so basically the Time Trapper), and that he's been playing Dragon this whole time. His plan is to destroy an Ultimen-empowered Infinity Orb to create a new Big Bang. This will create the universe all over, with the Time Being as its supreme ruler, its god. Oh, and those aren't really Ultimen; the Time Being has been forcing Clone Boy to create duplicates of the Ultimate Human Being to this end for a while now.
The Time Being walks in on this, and reveals how he expects to survive destroying the universe. See, he's not technically alive -- he's the temporal anomaly created when Grandfather Clock accidentally met himself in the past. He has the power to be anywhere and everywhere throughout time, but naturally this grew boring pretty fast.
As the Time Being prepares to end Dragon's life, Clone Boy turns himself into Ultiman in order to save his new pal. This was just an excuse to get close enough to duplicate the Time Being himself, which had the unintended side-effect of rupturing the Infinity Orb and putting the finishing touches on the Time Being's plan. The energy backlash will gradually erase the current timeline, starting with the most recent date and going backwards. Dragon escapes through the Time Being's time portal, hoping he'll be able to stop all this from happening by going to the past. However, the Time Being sends his lady friend Oblivia to follow Dragon and eliminate him.
There's a couple of completely meaningless stuff while Dragon careens through the time stream; you'll thank me for skipping it. Also, wasn't this thing supposed to be in color?
Anyway, eventually we hit... an apology and a summary of the five missing pages that didn't make the deadline. It says they'll print the missing pages in a future issue, but I couldn't find anything. Long story short, the Earth-B Blitz and Dragon head to the past before the era is erased, and meet Venus and Ultiman in the 70s. Also, Venus and Ultiman are dating or something; man, that's prescient, huh?
70s Venus? Obviously this business is nearly finished, then. Venus and Ultiman take Dragon to the moment of the Time Being's creation to stop him once and for all; the Brave and the Bold style Knight Watchman/Dr. Weird team-up from the end of #12. However, they're too late, and the Time Being starts wrecking everybody and everything. Oblivia shows up, too, to finish off Dragon with her kiss of death... until the Blitz pushes her into the Time Being. Her kiss erases him from existence, ensuring the universe's safety.
With that settled, Dragon has equipped himself with another Time Bomb (lifted from Grandfather Clock, no doubt) and heads back to his own time, with some stops along the way. Oh, and Venus takes Oblivia away to the Godrealm to get her help.
Here's where the cover comes in; back at the End of Time, Dragon finds, well, nothing, no sign of the Time Being's existence. He did it, he changed history... and before he can finally get home, he's attacked by the Pantheon of Heroes, as he's obviously their archenemy the Timebomber.
Dragon handles everything they throw at him until he sees Clone Boy and is momentarily floored. This gives the Pantheon the opening they needed to bring him down, and they're ready to lock him up and throw away the key once they do. Brain Boy and Tele Girl analyze him back at Pantheon HQ; it turns out that he's considered a great villain based on records of him fighting the RTA and the Badge. He's sent to trial, where he is found guilty because there is no one who can corroborate his "Time Being" story.
That is, until Ultigirl and Thunder Girl interrupt the trial, coming from the past to tell how they know Dragon's a good guy. Ultiman always told his daughter about how Dragon was a great hero, and Thunder Girl's memory was unaltered by the time shift because of her magic power source. Unwilling to doubt Ultiman's word, the judge changes the verdict to Not Guilty. Dragon is sent back home via a "time bubble" invented by Brain Boy, and finally defeats the Wicked Worm-possessed Mighty Man before hitting a bar with his cop buddies. The end... or is it?
I'm gonna go out on a limb and say that really is the end of this storyline, if not the Time Being himself, because I'm close enough to positive that he never showed up again, ever.
I do know that this isn't the last time Big Bang crossed over with Savage Dragon, though; members of the RTA were present at the wedding of Barbaric and Ricochet in SD #41, and would meet Dragon again in the Wildstorm-severing Shattered Image event.