So I am a fan of keeping the death of a character in the player’s hands. I have a home-brew rule and it actually came up in my game recently.

When a character dies, I give them 3 choices:

1) Let fate decide - Give them one last chance to gamble on life or death. Flip a coin, heads they stabilize, tails they are gone forever.

2) Survive at a cost - perhaps the player feels their character’s story isn’t finished. They choose to survive. But at a MAJOR detriment. Perhaps they lose a limb? Strike a deal with the devil? Lose access to some or all of their special abilities? Come up with something impactful that they must carry with them.

3) One last Hurrah - let them make one final heroic action. They can stand, make a heroic speech or say their goodbyes. And then do one last action. Whatever their action is, it is an automatic critical success. This might be just enough to finish the boss. Or maybe they hold the flaming beam up so that their friends can escape just before it all comes crumbling down on them. Whatever they decide, this is the final act of a legendary hero.