How come when the zombies are coming after you in the end you can use your gun and your hatchet, but not your shovel? The game clearly establishes that a shovel can kill a zombie. I have made it down to just one zed before, I really don't see why my shovel couldn't have taken it out.
A research option would be interesting. You could make buildings like labs to get research points. It could be like faith. It could allow you to unlock new unites, and new buildings. There could be a class that has a bonus to it.
It would be interesting if there was a way to invent new technology. Like there could be a research option and every few years you could research new technology. There could also even be a class that has a bonus to research. You could research how to make farms/producing buildings more productive, get more gold, or new units. So research would of course get even more productive in one-hundred year mode.
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