[Bug] Mob Spawnpoint Duplication Exploit

Reproduction steps:
1. Pick a target you wish to duplicate.
2. Kill the target.
3. Exit the zone, and enter the zone quickly (probably within 1 second, spam clicking).
4. Repeat a few times.
5. At a point, the target you have been killing will spawn when you enter the zone, in addition to the one already there.

Eventually, you will spawn an invisible version of the enemy at its spawn point. It cannot be killed, but will be targeted by your pet. It can use skills and attack you.

The select target will now begin spawning very, very quickly. Sometimes in groups of 5+ at a time. It seems they duplicate to a maximum amount of times, but I have managed to get 20+ one screen at once. Reproduction rate is 100%. I can demonstrate in-game if required.

You can also perform a very easy duplication in the cave during Locked Mementor, by spamming the switches until you reach the cap for mobs on screen(?)

While this isn't very abusable right now, it may one day be a problem.

Oh. When an enemy dies, I start a timer to respawn it. When the timer ends and if the map still exists, I spawn a new enemy. What I need to add is that the map must exist AND be the same instance than the last one.