Quote from: moneyfornothing on August 07, 2018, 06:36:35 AM

I think after the upgrade the yield will be much worse in mining game. At top level buildings life cycle will be 80 days and then it should be rebuild, which costs as much as upgrading building to that level. So it makes 10% return MINUS keeping efficiency at 200% cost more, just in gems but it is pretty much same thing. So we can forget 3.96$ in hour, it will take years to build mine to produce it.

That figure is for the very largest Mines. Smaller Mines will will see their levels last much longer and get a higher percentage ROI.

But even at the very largest Mine, you're complaining about a 10% ROI in 80 days (it's actually a little higher).

Were else (that's legitimate) is that even remotely possible?

You can also earn many thousands of Gems every day from the free Gems faucet, more than enough to take care of Efficiency and contribute towards your buildings.

And there will be opportunities to profit from trading gems. Back to those largest Mines (who will have fantastic cash flow in Coins), they can choose when (and if) to buy Gems, making even their possible ROI higher.

Sustainable, Profitable, and Fun Game > Unsustainable Magic Money Machine.