Training Knights from Guardsmen?
 

Is this upgrade path using the officer's patent possibly bugged? Actually, it seems like training guardsmen into anything might be bugged. It seems to require an order of magnitude more trophies than anything else. Training ONE knight from guardsmen takes, what, 600 trophies? That seems completely impractical since the only reason to train things is if there aren't places to hire them. And if you can't hire them, you'd need hundreds. 100 Knights from Guardsmen would take 60,000 trophies.

Maybe it is supposed to take 60 trophies and not 600?

In my experience, the trophy requirements for all upgrades are too steep to be practical, so I'm afraid it's not a bug.

I only train archmages into Necromancers. They are hard to find but not expensive to train. I have enough trophies to get them at max of my warrior leadership.

Anything else i think is impractical.