First off: Azteka. Yeah, the girl version of Aztek who only existed in the alternate future caused by Superman destroying a big heart-shaped rock that was actually a New God-created map of time and space, thus allowing Darkseid to take over the Earth. Why yes, this story was written by Grant Morrison.
The alterna-Earth's League consisted of her, a powerless Wally West, a ringless Kyle Rayner, Connor Hawke, Argent (of the then-current craptastic Teen Titans), the Atom, Aquaman, Amazo and Wonder Woman. I'm reasonably certain that we have the most names starting with A on any team ever, right here. Anyway, they've got a table in their post-apocalyptic clubhouse devoted to the relics of predeceased members:Left to right: Steel's (hilariously long) sledgehammer, Doctor Fate's (hilariously ventilated) helmet, a chunk of Robin's tunic, Captain Marvel's man-bracelets, Mister Miracle's cape and mysterious metal bangles, Jack Knight's cosmic rod and Superman's chest logo circa his Breakin' 2 era.
We're told that Superman committed suicide after mercy-killing a roboticized Lois Lane, Martian Manhunter was thrown in a particle accelerator so as to destroy every single atom in his being and it's pretty clear how Fate was killed, but the rest of the deaths are left to the reader's imagination.
There're probably half a dozen deaths over the course of this storyline that merit inclusion on this list besides Azteka's (Darkseid's chief amongst them), but this one is the most utterly insane.
Azteca and Argent are dispatched to the moon so as to shut down Darkseid's Zombie Factory while the rest of the team (plus a beaten-to-Hell Batman) confront the big D himself in Las Vegas. When Argent is mortally wounded, Azteka remembers that Grant Morrison created her and, fittingly, her suit is powered by abject madness.She done flipped the switch.
Dying in such a manner? Totally validated by the befuddled look on Darkseid's face.