Not exactly sure if this is the right place to be posting this, but it seems appropriate enough. By now I'm sure the lot of you know about the MVM example scripts mvm_example.pop and example.pop, but I have a few questions concerning them and mvm_upgrades.txt . Firstly, in example.pop it states the following at the very beginning of the first wave's code: I can't get this to work for the life of me. It seems simple enough. Does this simply not work or am I doing something wrong? Also, the first two lines in mvm_upgrades.txt are ..yet it doesn't exactly state how to do this. I've tried scouring through items_game.txt for any evidence of tags or groups, but what I found led me nowhere. Changing values in there didn't quite work as well as I'd hoped either. Furthermore, you can edit mvm_upgrades.txt and everything works out great.. until you try to add/change an attribute on one of the upgrades. Most of the time it simply disappears from the in-game shop. My question is, how do I go about assigning attributes and items to groups? Anyway, editing .pop files has been a ton of fun so far. I'm curious to see how creative people get with them.