Last War Tricked Me With a Math Game Then Pushed Paywalls Hard

I downloaded Last War: Survival Game two months ago after seeing an ad for a math-based zombie game that looked like it might be enjoyable. It was a great way to pass the time as I waited for my car to be fixed. At first, it was just what I thought it would be: I was using numbers to kill zombies, which was strangely satisfying. But the game shifted completely after roughly 10 minutes. I suddenly had a base, timers, upgrading systems, and strange rescue missions that didn't make any sense. Things moved far more slowly unless I spent money or waited days for updates. I also started getting a lot of adverts and forceful offers to buy power-ups. It felt like a bait-and-switch, and it grew monotonous quickly.