Quick Trigger Help please

[chiodos92307]

im making a map where when you create a building, it spawns a unit in the corner of the map and it masses towards the other team.
depending on how many of one building u build, depends on how many units spawn and keep massing

you build 1 barrack, it spawns 1 rine that masses towards the other team
you build 2 barracks, it spawns 2 rines that mass... ect
up to 4


so i need a trigger that every 10 seconds it will continue to spawn the same amount of units depending on how many buildings i have

if u need more detail, feel free to ask.

thanks!laugh: