Pick by UID and then use UID to set unique behaviors if they're static enemies (i.em are predefined per map)
You can do either of these.
A, Use this action to pick by UID, and be sure to do it right after an enemy is created (if not created on runtime):
int(Enemy.UID)
B, Or just look at an instance in your editor to get the UID you want.
Also, you should learn to use families for managing enemies, yes, it makes for a lot cleaner design.