It started well before this, but one of the most publicized, shameless, and money grabbing "deaths" in comics that really killed the concept of death, was the death and return of Superman. It sold like gangbusters and then his return(s) sold even more, showing publishers that they can feed fans whatever they want, they'll still buy it. Go ahead up the prices, make it a limited print run, we don't care, KILL EVERYONE, we'll see 'em next year.
With death there is always resurrection (at least in comics) and these are the worst, silliest, dumbest, most ridiculous resurrections in comics. Vote up the worst comic book resurrections below.
Obscure plot device villain The Queen decides she wants to have a baby and that Spider-Man is just the guy for the job. So, she kisses him, which impregnates him. Somehow. He spits. There's so much weird awkwardness here we have to move on. Unfortunately, that mouth pregnancy doesn't just impregnate Spider-Man, it also turns him into a giant... spider. Because science.
The spider that is now Peter Parker is legitimately a spider, so it doesn't know what's going on when The Queen tells it/him that it's pregnant. It starts making spider sounds and doing spider things... then he starts to have a seizure and dies. They don't explain this. She seems surprised as well, so it wasn't intentional that he died. The Queen leaves, crying. Then, he BIRTHS FROM HIMSELF. Peter Parker, a full grown, naked man emerges from the dead Peter Parker spider thing.
Look at that picture. That is art. That exists, you guys. Alfred was crushed by a boulder while riding his motorcycle. Wow.
Realizing the error in their ways (they killed Alfred to bring in a character from the Adam West show) DC brought him back by... well, someone at the cemetery heard him snoring. Snoring. Let that sink in. Batman, the world's greatest detective didn't detect that his only family wasn't dead. Oh, and also what kept Alfred alive after you know, being crushed alive, was his love and devotion to Batman and Robin.
He was zapped by Darkseid, resulting in a very dead (like, just a skeleton in a costume dead) Batman. Superman carries his costumed corpse away with tears in his eyes. Tests on the skeleton proved once and for all that this was Bruce Wayne's (DEAD) skeleton.
But you see, the thing about that skeleton was it was his... (ugh) clone's skeleton. (That's right, they Spider-Manned AFTER the clone saga showed them not to.) The real Bruce traveled back in time for some reason and lived many Bruce Wayne lives like Old West Batman, Caveman Batman, Pirate Batman, and a bunch of others. He came to present time (somehow) and had a deeper love for his son (who was soon killed) because he never gave up on his dad.
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Spider-Man's precious Aunt May. The only parent he has left, tragically dies, seemingly of natural causes while Peter and Mary Jane are by her side. It's beautiful it's well handled, it's important. Spider-Man can't save everyone.
Nah, just kidding, we kidnapped Aunt May! That wasn't even her, that was a "genetically modified actress" who we... paid to die...? Osborn, wanting to destroy Spider-Man at his core, convinces him Aunt May is dead, then for years strings him along, until she comes back with a "device that would detonate a series of gene bombs" if removed. (What's a gene bomb!?) But then Reed Richards gets it out and we have Aunt May back... who conveniently remembers nothing about years of captivity and is now... really... really... old.