You decide to lower the taxes.
1112 AD, Spring
While your soldiers march south, the alchemists return from the north, bringing money from Queen Dogethe.
"We were able to teach the Queen's men how to create Fireblood and how to shape machines using it. She has sent with us the remainder of money agreed to in the treaty." They also bring news and rumors from the north; the bearded pirates of the Saltsand Waters, the Albionese, have launched an amphibious invasion backed by attack from the mountains, taking Kingdom of Helliste by surprise in least convenient moment for them, as recently the Hellistes had several rebellions occuring in past three years.
1112 AD, Summer
The Fireblood caravan once again arrives in the capital, and the ingredients are paid for with gemstones.
In relation to Fireblood, the alchemists, both young and old, ask for audience. The royal alchemist steps forward.
"Greetings, sire. I wouldn't interrupt your hard day at work if it weren't for the young apprentices of ours." The young men take off their greenish berets and bow to you.
They explain that they have a novel idea of smaller Fireblood machines that could be wielded by two people, or even by one strong enough person. It would require certain re-designs and most of the money currently devoted to manufacture and maintenance of Thundercats and even Blackhearts would be directed to this new project.
They apparently stumbled upon this idea after some very innovative youngsters decided that its next logical step after the huge and slow Blackhearts were replaced by Thundercats, which are smaller yet much more powerful after all.
The older alchemists believe that this would be waste of funds, especially that Thundercats' feasibility haven't been yet tested in actual war, and thus they would prefer to fund what currently works rather than run after every single idea their apprentices come up with. You listen to murmur of the audience room; it seems your courtiers agree with the older alchemists.
A) But think about it! Every soldier carrying a miniature iron tube of fire and thunder! This will be grand! We will be grand!!
B) On the other hand, we should stick to what we have and be content with that; there will be time for innovations later.