You don't need to do that.
When you put an entity in WED, you can assign an action to it, and it will behave independently of any other entity that has the same action assgined.
To do that command you mentioned (Entity1.x += 1;) you will need to use something like this (corroborate with tutorials):
First, in WED, set each entity's skill1 to 1,2,3... never repeating.
Code:
//before any function, at the script start:
define Id, skill1;
//then, inside the entity's action:
...
if(my.Id=1){Entity1=me}
if(my.Id=2){Entity2=me}
Hope this helped.