I have this kind of level system. I have a timer that waits for some time. (in this case 10 seconds, but later it will be more like 60 seconds)
Every "level" labeled sprite families has different enemies and when the timer goes off, the game will start spawning harder enemies, or old enemies with different rules. That's the basic idea of this.
I think this should work like this, but still it does not work. And I have no idea what's wrong with my events.
Now what the game does, it spawns enemies from Level_1, but when the timer (10 secods) goes off, it stops spawning anything and the game stops working. Of course half of it works, it should stop spawning level_1, but i have no idea why it does not activate 2th_level -group.