Doomsday was an absurd monster cooked up by DC's editorial department when they had nothing better to do and decided to bite down hard on a lighter.
You could say that the inevitability of that piece of shit, Laughing Man, had already begun to show the moment Doomsday was created. Power-scaling Russian dolls would always hit a wall eventually, and DC's editors chose to smash through it by piling on more lore.
If The Batman Who Laughs was the product of editors nesting intelligence within intelligence, then Doomsday was the pinnacle of nesting brute force within brute force. Both kinds of nesting shared one trait: they had to create some premise that gave the character no upper limit.
Laughing Man was the classic god of premonition. No matter what had been drawn in the first half of the series, as long as they later added the line, "Laughing Man predicted your prediction," then whatever he did afterward was perfectly reasonable.
Doomsday, on the other hand, evolved. No matter how powerful its opponent was, Doomsday could absorb their abilities and evolve, and its Evolutionary Ability had no upper limit.
However, the martial faction had a fatal flaw compared to the intellectual faction: they could be beaten to death while relatively weak. So the editors' clever little brains flashed with inspiration, and they gave Doomsday another bizarre premise—the Doomsday Spore.
Simply put, this was a special parasitic ability that adult Doomsday could use. It could release destructive spores, and the life force of any living creature within their range would be drained by Doomsday. Once someone was contaminated by the spores, they would become Doomsday's host.
After Doomsday's main body was killed, as long as even a single Doomsday Spore remained, it could multiply within a host, consume the host's flesh and