Script 1press button:
History [summon=This is an example]
Mob script that i forgotten
Script2put this in entry script in the arena zone
If
HasHistory [summon] [ player ]. ...
Then
Else
Teleport.....
Notify......
Script3put this in Mob dead script thing
Teleport....
History [summon] [clear] [player]
Notify.......
You Can change this scripts whatever you like.