BlackEvil, I wanted them to rot, just slower.
Hank, I tried to get ur way to work, but it didn`t work out too well, like units are constantly created in my map, and constantly die, so if I am to use this "Add 60 second to rotting" I`ll have to use it at least every 61 seconds, otherwise it would just constantly add more roating time to the units already roating. And thanks for this “Roating state” tip, woah, didn`t ever thought such thing was possible.
So I went the other way (expanded on my food on corpses idea)
Every unit is created with 2 food on them. And every 60 seconds I ran effect Decrease food by 2, for All Units 1-999, State FoodRoating. So units die and stay on the ground, and every 60 seconds that effect fires and these old corpses disappear.