I think this was the first game I ever 100%ed ^-^' Honestly, it's really good, and it holds up pretty well imo. I'm not normally a fan of the tower defense genre, but idk this just hit different. The levels in the campaign are very well executed for the most part, and pretty much every gimmick changes gamplay substantially enough to keep things fresh. The side content is also has no right to be as fun as it is. This really was the peak of mobile game design before the medium went down the shitter with in-app purchases and the live games-as-service model. If you have never experienced this game somehow, then I totally recommend giving this a shot.