Noted. Will learn from your loss.
You want to use Attached Units when setting sieges and filling towers, when ever you can. The reason why is because Attached Units can be regenerated by the Military building they come from [are attached to]. Unattached units don't have a Military building that can replace them. You will use plenty of unattached units as you play, because there is no way to produce the numbers you will eventually need, even with something like the Alcatraz Great Building, or Guild Expeditions for examples, adding more to your total supply of troops.
Don't worry about using your Unattached Troops, but also know when it's better to use Attached over Unattached. You always want to use Attached over Unattached when you can make the choice if units of the exact same type. Because when your units are defeated, you have the option of regenerating them with your military buildings.
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