It is more convenient and time-saving to make a system that consumes 10 cards rather than using 1 card to recruit 1 soldier. And now deleting one by one is painful and takes a long time. If you develop a system of selective deletion, we’ll be able to select the ones we want and send them back at once.
I think this idea has already been proposed by a number of users before I speak. Now I have 600 bronze cards, but it’s a hassle to spend.