Hero leveling during the first 2 weeks.

And by the 3rd day, the pace is already lost. On the first day, armies from two heroes are enough to break through nearby armies. Specifically, for the Mage, it's best to have Nur, Narhiz, or Hafiz, in general, someone with ranged attacks or a lot of gremlins. The most important thing here is to get lucky with the guards – to avoid red archers or upgraded sprites, as they require a special tactic. Of course, you need to place mages, sometimes gargoyles are brought in, and golems, if the cover for the gremlins is running out, or you need to hold back the enemy for a long time. On the 3rd day, you can even take out the Necropolis, even if there are 5 liches there. The most dangerous are casters and powerful archers; here, it depends on how the initiative plays out – this determines the losses, although you can attack with single units and powerful artillery. In fact, on each map, the actions are probably slightly adjusted; sometimes it is beneficial to clear out weak nearby neutrals and gain experience from chests, and sometimes on the 3rd day, you already need to go into an adjacent area and may not return for 3 weeks.