Huh? I don't get it. What do you want us to help you with in your trigger? Do you want to manually give experience to heroes through triggers?
If that's the case, then you need two variables. To be more precise, an integer array with a size of 2(zero counts) since you want three neutral players giving different amounts of experience and a group. A group, because you'll need group of heroes to give the experience to. Name the integer variable something like "HeroExpGive" and the group "ExpGroup" or something so they're easy to recognize. So set the variables like this:
Then you just have to set them as needed. For the group, we'll only want heroes to divide the experience by AND we only want heroes that are enemies of the dying unit. Then we need to set a certain range of how far the heroes will need to be to get the amount of experience. I'll use 1500; You can use whatever you want(If you want the ranges to be different for each neutral player, make the group variable an array, too).
Trigger:
Set EXPGroup = (Units within 1500.00 of (Position of (Dying unit)) matching ((((Matching unit) belongs to an enemy of Player 12 (Brown)) Equal to True) and (((Matching unit) is A Hero) Equal to True)))
For pure example, if you want HeroExpGive[0] to give exp. equal to the creep's level and HeroExpGive[1] to give exp. equal to two times the creep's level, and then you want HeroExpGive[2] to give exp. equal to five times the creep's level, then...
Now, all we have to do is set up the conditions. I think it's better to use If/Then/Else Multiple Functions.
We'll repeat that trigger above for the two other neutral players. Now, let's put everything all together into one, complete trigger.
You don't need to clean up global variables and it's as close to MUI as GUI triggers can get, because all variables are declared at the beginning of the trigger and there are no wait functions, so the trigger should work fine(can't test it; it's too late for me and it's a school night).
If I did that no reason, oh well. And I'm absolutely sure that there's a way to clean up that trigger I just made. Oh well for that, too. I know that you guys say that we shouldn't do everything for the beginners, but we all started that way. Everytime I see these kinds of questions, I get a nostalgic feeling of the past.