The scenery/buildings generate ancient runes for you to collect. That you know, more than likely.
But did you know this? There is an optimal way to collect them.
If a building says it has 3 ancient runes for you to collect then it might actually have 3.95 ready for you. It will only give you 3 if you collect it now though, since it rounds down. If you wait several more minutes instead, it will give you 4 instead of 3. It might not seem like much, but it really adds up over time.
So how do you know if it’s worth the wait? You look at the silver. If it generates 60 per hour and has 239 ready for you, then it’s been working for almost 4 hours (239/60). If you wait just one minute more, you’ll get 240 silver and exactly 4 ancient runes. You won’t lose any due to rounding.
But wait, there’s more. There’s an additional unadvertised perk for those who subscribe with the SuperPass. When you click on the magnet, it adds up all the ancient runes from all the buildings, including all the fractional parts, and then rounds down. That’s a big win over rounding each one down individually. So, you don’t need to worry nearly as much about the rounding if you subscribe.
And for those who really like to optimize (like myself), you can wait to click to on the magnet for its optimal time. I will explain that only if someone is curious and really wants to know.
If this is way more than you want to think about (understandable), then I still have some easier and more general advice to follow. The less often you collect, as long as you don’t max out the capacity, the better. Avoid randomly collecting when only one ancient rune is available, or you might miss out on another one every time you do it, due to rounding. Better to wait until you have more ready to be collected.