It's hard to say how valuable defense will be if no one comes to your Aether Keep but it may become the only way to come out ahead if we continue to be so starved for resources. For now, I still have 0 defense games.
I say it'd be pretty valuable to have a good defense because when your tier is high enough, you'll start lowering, and if you get more defense losses than offensive victories, you're not progressing.
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