The last time a near TPK ended up happening only 1 party member was alive and they had enough scrolls of revivify to revive all but 1 party member. That remaining party member challenged the avatar of Death to a 1 on 1 fight to come back to life. They barely succeeded but they ended up winning.

Basically I've got a lot of extra rules about things if a player end up dying that they can pick from in the event of death. I have them pick it during character creation as part of adding more depth to their characters. It usually ends up being pretty cool.

Funnily enough my players usually only get close to death when fighting creatures instead of intelligent beings. They seem to have a knack for it at this point.

Well planned encounter that the party comes across on their current quest?

Smashing success, barely an inconvenience.

Random encounter from random encounter table

Fight for their lives, knocking on deaths door.