Tactics for Dungeon.

Difficulty: Do you mean the difficulty level, or what specifically is difficult for me? If it's the former, then the difficulty is the Queen. And there are many things that are difficult for me... First of all, I would like to know how to break through the "tough" guards of passages and treasuries in the early stages of the game without relying on archers (I'm more used to playing with archers) and without suffering serious losses. When should I upgrade harpies: as early as possible, or can I even wait until after the first week (but then who should I use to fight in the first week:confused:)? What shouldn't I build in the Dungeon at all (to save resources)? If there aren't at least 2-3 external "native" outposts, is it worth developing in my native castle, or is it better to do it in the first castle I capture? How many heroes should I buy in the first week (is the principle "the more, the better" always justified)? And these are probably not all the questions that have accumulated.
If it's not too much trouble, help a newbie.