Dungeons & Dragons

Haven't had a character die in a long time, as I am mostly a DM by this point. But my most memorable one was back when I was playing 3.5, we had a TPK, that was entirely the fault of 1 player.
He had died last session (self-inflicted) and was bringing in a new character. We were in deep caves, fighting goblins and their kind, and he decides that his new character was to be a drow. This would be the perfect place for him to show up, because Drow love caves, right?
Unfortunately his first action in combat is to try to get himself advantage by casting darkness on the bonfire in the middle of the room we were in. What he didn't consider was
a) All other light sources had been snuffed out by a goblin ambush that we were currently fighting
b) he was the only PC with darkvision.
c) Darkvision doesn't see through magical darkness.

Needless to say, we were slaughtered pretty quickly and he shrunk off in shame.

You know, in ~14 years of playing, I don’t recall ever having one of my characters die-die. (My current Pathfinder fighter gets knocked out and almost dies virtually every session, but we have a healing cleric and a sorcerer with a couple healing spells to keep my dumb ass alive and so far, so good. ❤️‍🩹)

My poor spouse, on the other hand, lost his very first character at a pretty low level. 4e cleric got critically glue potted by a kobold and then toasted by a dragon. (He later looked more closely at the rules and realized the DM may have made an error in determining ongoing damage from the dragon’s breath weapon, but ah well—such is ttrpg life. (And death.) Made for a memorable conclusion to his first character’s brief adventuring career.)

My first character death was in a kind of gritty setting. My character was a wild magic sorcerer, we got into our first combat and the spider-like enemy lept at me. This was only my second character and my first was an artificer armorer tank so I didn't even think of being able to disengage. I tried to kill the spider, natural 1 miss. It then attacked me on it's next turn and got a natural 20. Did enough damage to fully kill my sorcerer in 1 hit.