You can add me to the list that has learned something so far. I never knew you could "steal" the gems from mercs. I will have to remember that one. I have tried to take their magic items before with no success and figured the gems worked the same way.
I am sure it has been mentioned before, but another thing that can help in controlling how many gems your commanders use each battle is to store them on a non-spellcasting commander in your army and just hand over to your casters the amount you want to allow them to use before each battle. This helps reduce waste and extra trips back to a lab to replenish gems. I played some Man for a while and it finally occured to me to try this so they wouldn't burn up all the gems in one battle casting Wind Guide, Swarm, and other spells.
Good luck with the rest of the AAR
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