Cypher, a mutant with the power to translate languages, died. Warlock, a techno-organic alien, died. Their corpses somehow combined and came back as Douglock.
Professor X died. It was later revealed that it hadn’t really been him, but a shapeshifting mutant posing as him.
Dan Ketch, the human host of the second Ghost Rider (the motorcycle GR’s not the cowboy ones) died. Dan would transform when innocent blood was spilled. When a serial killer tore out his throat, he killed Dan. But, triggered the transformation into GR. Eventually, GR transformed back into Ketch who was saved by Dr Strange.
Robot Man of the Doom Patrol. He started his career as a superhero when his car crashed. Niles Caulder was able to save his brain by transplanting it into a robot body. Then, a villain called the CandleMaker destroyed his brain. Fortunately, Caulder had backed up Robot Man’s mind on disk. A new RM was built, using a hard drive. Eventually, beings from another dimension gave Caulder a fully developed, but blank, human brain and RM’s memories and personality were transferred to it. (Then Rachel Pollack became obssessed with menstruation and the series was cancelled. Then, it was picked up as a more normal but still quirky series. Then, that was cancelled. Then some morons decided to let John Byrne do a Doom Patrol series so that he could crap all over it).
The Vision- John Byrne crapped all over this poor android. He had him disassembled. When he was reassembled, he had no emotions. A later writer with a working brain restored the Vision to his usual self.
Ghost Rider 2099- Poisoned and surrounded by members of a rival gang, Zenshiro Cochrane decided to deny them the data stored in his neural implants by burning them out. He uploaded his entire mind into the net. There, a strange agency found him, built him a robotic body, downloaded him into it and sent him into the world.
The Flaming Carrot- He fell to his death while rescuing a cat. His corpse was found by trashpickers, who exhibited it a flea market. The Artless Dodger recognized it and bought it cheap. He sold it to the Carrot’s enemies, the Hudson Dusters. The Junior Carrot Patrol was able to retrieve it. They gave the corpse to FC’s friend, esteemed mad scientist Professor Heller. He subjected the body to various treatments. In the end, it was a matter of the Carrot’s will to live. Playing Lorne Green’s lyricized version of the theme to Bonanza revived the Flaming Carrot.