how do I do that and what does that mean?
From how to play
"Capitulation
It allows a certain Empire to defend itself from the attacks of another for a 168 hour period. During this period, neither the capitulated Empire nor the attacking one can send attacks to each other.
Player “x” has the right to capitulate to player “y” solely if in the 48 hours right before the capitulation “y” attacked “x” at least once, and “x” didn’t attack “y”.
You can capitulate up to 10 times in a 168 hour period, completing the conditions listed above, of course. The first is free, but every following capitulation costs 10 diamonds more than the previous one.
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