How do I make enemies that re-spawn?

I am making a top down Zelda like game and I am trying to make it where my enemies will reset or get destroyed when you leave the room but will re-spawn if they have yet to be killed by the player. Thanks in advance for any help I get.

Hmmm, this is a good question. I'd be interested to know a proper way to do this as well. My only guess would be doing something along the lines of setting up an instance variable on a type of enemy, name the variable "dead" or something. Then, each time you kill one of them, check their UID and set their "dead" variable to true so, if dead = true --- destroy enemy.

I'd be interested to see what other people have to say too.

yeah I have my enemies in a family so that I had have their family keep track of all the hp instances of each enemy