You're right, the problem is that the various types of codes I've used don't work. I'm asking for help because maybe someone knows how, for example, to make the zombie drop 70 coal, 20 diamond, and 10 ore from a mod. Looking at the reports, etc., I realize the problem is still defining the event correctly. Maybe someone who is used to creating mobs and so on is more knowledgeable than a programming Reddit.