So I was on Battlenet recently, and some guy (who was a total jackass) was bragging about his superior triggering capabilities. He told me that I was a newb because I didn't know how to trigger the following system: it turns out you can detect the location of a unit "after" its death. So, let's say you have 6 Broodlings in an area, and each time one of them dies, you have a location move over its corpse.

I just don't know how its possible to detect a dead corpse, can someone explain how, if possible?

You follow them until their death.

some units also hang around with 0hp for ~1 frame, possible to detect preplaced units with EUDs like this (or not even preplaced if you have even more insane index detection systems in place), however triggers run every 2 frames so it's very unreliable, moreover you're going to have a fairly tough time getting a location on the unit, though it is possible

Following the units with locations is most common for things like this

You can't follow separate Broodlings owned by the same player in the same area, they're too fast and will escape the LID.

If you give each Broodling to a different player, or keep them in separate areas, then it's possible, but that's not helpful for many situations.

The person most likely thought they knew what they were talking about but didn't, or simply wanted to taunt you.

I'm pretty sure the concept you're looking for is in this old topic: http://www.staredit.net/topic/6619/, which supplies this proof-of-concept map: Duplicating Marines. But that technique isn't guaranteed to work, and it will fail 50% of the time (depending on which frame the unit dies on).

Because the system is unreliable, it has fallen into obscurity, and it sounds like the person you talked to took pride in knowing a near-useless quirk. Let him have his moment.

Okay well that confirms my original judgment. Cheers guys.