Let me give you guys some concrete information.
Clearly the trigger that creates one civ is activating twice, once for the human player and once for the computer, because they both own a copy of the trigger.
The obvious question:
"The dropship was killed by the first trigger, how can the second trigger activate?"The Kill action does not immediately kill units, they are actually killed after the trigger cycle is over. You can detect units that have been killed this way for the remainder of the trigger cycle. The dropship is still "alive" when the second trigger's conditions are checked.
The solution: Use remove instead of kill. Units that are removed are deleted instantly, and cannot be detected later.
The other "solutions" are just work-arounds. They may appear to work, but they do not address the actual problem.
The kill action is the problem, not the trigger order.QUOTE
Every two seconds the entire list of triggers will be executed. When this happens the triggers will be checked in the order that they are listed in the Trigger Menu -> Players tab. That order is: Player 1 Player 2 Player 3 Player 4 Player 5 Player 6 Player 7 Player 8 All Players Force1 Force2 Force3 Force4
Ignore this order, it is wrong.
Triggers execute from Player 1 to Player 8. There is nothing else.
The Forces and "All Players" are not legitimate trigger owners. When you select any of these, the triggers are simply assigned the the corresponding players.
For example: Checking "All Players" is equal to checking P1, P2, P3, P4, P5, P6, P7, and P8 individually.