[Spell] I need help with a trigger

[Kunkka]

I need help with a trigger, the ability is to create 1 unit, but when there are more than 3 units, the first is removed and the second becomes the first and so on

 

[Warseeker]

What do you mean ''when there are more than 3 units''? Within an area or something?

 

[Alok]

You need to store each unit into a variable:
1st unit created - Set Variable "1st unit" = Last created unit
2nd unit created - Set Variable "2nd unit" = Last created unit
3rd unit created - Set Variable "3rd unit" = Last created unit
4th unit created trigger - Remove "1st unit" (variable), Create the 4th unit, Set Variable "1st unit" = Last created unit
5th - Remove "2nd unit", Create 5th, Set Variable "2nd unit" = Last created unit

So you'd need 3 triggers:
1st unit created trigger - Remove "1st unit" (variable), Create the 1st unit, Set Variable "1st unit" = Last created unit
2nd unit created trigger - Remove "2nd unit" (variable), Create the 2nd unit, Set Variable "2nd unit" = Last created unit
3rd unit created trigger - Remove "3rd unit" (variable), Create the 3rd unit, Set Variable "3rd unit" = Last created unit