Blue crystal

I don't know how to attach a save file to a message. And also, don't try to mislead people about Seraphs.

Added 12 minutes ago
Yes, regarding the troops of my main hero - Vitya the machine gunner. The monthly increase of Adepts is 7, plus 20 from training, which means 108 per month. Multiplying by 5, we get 540 (I had 541). I practically didn't lose any Adepts or Archers. As for Archangels and Paladins, their losses were minimal, maybe about five of the former and fifteen of the latter. So, it's unclear where the author gets the figure of "100-200 units" and generally concludes that my main hero's army was small after 5 months of the game.

When creating a message, select Advanced mode; there will be a button called "Manage Attachments."

Regarding the calculation, I might have been a bit hasty with the number of Archangels, here are my estimates:

5 months = 20 weeks. One week doesn't count, as it's without a Castle, leaving 19.
One month after capturing the Castle, it's realistic to build Angels and upgrade the Castle, so the number of Angels from the Castle alone will be (20 - 5) * 2 = 30.
Two months after capturing the Castle, or even sooner, it's realistic to capture a level 7 building. Since the Castle's growth increases by 1, this all together gives an increase of (20 - 9) * 2 = 22. In total, approximately 52. This number can be increased slightly.

As for the Knights, here's my opinion. But I prefer to train Knights, reducing the number of Monks.
Knights are built about a month after the start of the game, and the building can be captured in one and a half to two months. In total, this gives (20 - 4) * 4 + (20 - 8) * 5 = 104. It's possible to train them normally after 3 months (or earlier). Alternating weeks: 1 week - 10 Swordsmen -> 10 Monks -> 10 Knights, 2 weeks - 20 Monks -> 20 Knights. In total, in 2 months, you can train 4 * 10 + 4 * 20 Knights, or 120.

For gold, it would be good to buy Ellaine in the tavern and transfer all peasants, capture 2 gold mines, there is a chance to get gold in abandoned mines and artifacts + resources / rewards, and try to give all secondary heroes leadership or luck on the road to manage the treasury.

Of course, in reality, it might not be so rosy, but it is still feasible.