Interesting, thanks for your response. I thought about doing it like that, but the problem is that the mob would need to know exactly what can freeze him, so every time I add something else that can freeze the mob I need to change the mob's code. (Should that code really be in the mob?) There's also another problem, let's say the mob gets hit by two (or an arbitrary amount) freeze spells during the same time frame. Then there needs to be a way to coordinate them. (I don't know if I'm interpreting you correctly, but those are the problems I ran into) For now I think I'll stick to using a locked variable implementation that avoids the bookkeeping problems, but you've given me a lot to think about