Spawn system

The idea is pretty simple: place Points where you want your units to spawn and then use random integers to randomize the spawn.

Trigger Reference

http://vgshorts.com/BBCode/BBCode3.php?ID=97

Spawn system
   Events
       Timer - Every 15.0 seconds of Game Time
       ------- This is the interval of time at which the units will be spawned.
   Local Variables
       Unit Type = 0 <Integer>
       Random Point = 0 <Integer>
       Selected Point = No Point <Point>
   Conditions
   Actions
       Variable - Set Random Point = (Random integer between 1 and 5)
       General - If (Conditions) then do multiple (Actions)
           If Then Else
               General - Else if (Conditions) then do (Actions)
                   Else If
                       Random Point == 1
                   Then
                       Variable - Set Selected Point = Point 001
               General - Else if (Conditions) then do (Actions)
                   Else If
                       Random Point == 2
                   Then
                       Variable - Set Selected Point = Point 002
               General - Else if (Conditions) then do (Actions)
                   Else If
                       Random Point == 3
                   Then
                       Variable - Set Selected Point = Point 003
               General - Else if (Conditions) then do (Actions)
                   Else If
                       Random Point == 4
                   Then
                       Variable - Set Selected Point = Point 004
               General - Else if (Conditions) then do (Actions)
                   Else If
                       Random Point == 5
                   Then
                       Variable - Set Selected Point = Point 005
       Variable - Set Unit Type = (Random integer between 1 and 6)
       ------- The use of If-Then-Else is just to show that both methods work.
       General - If (Conditions) then do (Actions) else do (Actions)
           If
               Unit Type == 1
           Then
               Unit - Create 1 Zealot for player 0 at Selected Point using point facing (Ignore Placement)
               ------- Notice the point at which the unit is created is the "Selected Point" Point variable.
           Else
               General - If (Conditions) then do (Actions) else do (Actions)
                   If
                       Unit Type == 2
                   Then
                       Unit - Create 1 Sentry for player 0 at Selected Point using point facing (Ignore Placement)
                   Else
                       General - If (Conditions) then do (Actions) else do (Actions)
                           If
                               Unit Type == 3
                           Then
                               Unit - Create 1 Baneling for player 0 at Selected Point using point facing (Ignore Placement)
                           Else
                               General - If (Conditions) then do (Actions) else do (Actions)
                                   If
                                       Unit Type == 4
                                   Then
                                       Unit - Create 1 Roach for player 0 at Selected Point using point facing (Ignore Placement)
                                   Else
                                       ------- Notice I am not using the integers 5 and 6. This is simply because I wanted those two integers to represent a "No spawn" situation. More empty integers you'll have like this, less chances the spawn system will actually spawn a unit. This is just a personnal choice.

Please take note that there are comments within the trigger above.