Powerups are all invincible, except resource powerups. Resource powerups are unplaceable by triggers. You'll have to use a unit of some kind, or figure out a way to achieve what you want with powerups (you can have them be killed when a unit walks up to them or something).
Binary countoffs are a method to efficiently produce any number, since binary can produce any number (did you know you can count to 31 on one hand, and 1023 on two hands?) easily.
your triggers will look something like this:
Deaths of "check food" is 1 <- just a condition to start the check food, set it to 0 at the end of the run so none of these triggers will run again
Command at least 1 scv <- binary countoff, also check for at least 16,8,4,2 and possibly higher.
then
Give 1 scv to other player <- another countoff, use same numbers
Add 1 deaths of "sum" <- another countoff, use same numbers, this one is your total count of workers
Repeat for drone, probe, civ, and change all the numbers to 16, 8, 4, 2, and higher if you want more than 31 counted.
Deaths of "check food" is 1
Deaths of "sum" is at least 1
bring at least 1 "food" to location
then
kill/remove 1 "food" at location
subtract 1 deaths of "sum"
If you have no "sum" left, you are in the clear. If you have any "sum" left, you didn't have enough food, and you need to kill off some stuff, or something. I don't know what you are planning on doing.
Make sure you read up on binary countoffs, and any other links that are to the wiki in this thread. If you still don't know what to do, write
in detail what you are trying to accomplish.
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