A small number of heroes – I agree, it's a big drawback... The number of heroes is directly proportional to the number of resources collected, especially when there are many of them lying around + by the beginning of the second week, you can pass monsters to the main hero in a chain, who is already 3-5 days away from the home castle at this time...

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By the way, taking this opportunity, Happy Birthday!..=)):smile12:
Happy 103rd anniversary... :D Judging by the year in your profile, 1907...=))

Thank you!
As correctly noted, you can transfer troops from the castle to the forward hero using a chain of heroes.
The correct game plan for the second week in this case was as follows: the forward hero goes up, the hero from the castle buys troops, passes them to the second, he passes them to the forward hero. The battle with the trolls should follow this scenario: stone skins on upgraded mages. They shoot at the trolls. Pigs go forward. Trolls shoot. Birds block the next two troll squads. The last squad(s) of trolls shoot, halflings shoot, then without losses, you just need to monitor the amount of health of the birds. In principle, in the worst case, the losses will be 1 archmage and 1 bird, but most likely the battle will pass without any losses at all. After this battle, the hero goes forward to capture one of the computer's castles no later than the first day of the third week.
After that, the plan is as follows: the main hero goes to capture the next castles, the hero from the home castle with the army of the second week goes to help him, if necessary, crushing the computer's heroes and capturing castles, if there is enough strength, in the captured computer castle, reinforcements are bought, and this hero clears the territory and helps the main one. On day 141, you need to finish the game, otherwise there is a risk that it will drag on.