Auto-translated
I already wrote. We build a converter with 1-1-1. We transform the right hero's and our zombie's abilities. In total, we get 2-3 stacks from Galtran + one stack from our own Castle, plus the transformed abilities of the right hero, which gives us about 100-120. We take chests for experience. (only develop Necromancy) + with 1-1-2 amplifier. In total, you can gain 20-50 per day. By the end of the week, you can reach 400. If you're lucky and there's a 1-2 resource nearby, take it, and the problem of a small movement range is solved.
Greetings to Guru Forrest, guys, listen to what he says, because he plays Heroes like a pro and knows what he's talking about (although he doesn't play here, but on Heroes.by, it's very useful to read the game reports there, you can learn a lot of new things).
Regarding the topic: it's difficult to kill Galtran because, as Forrest described above, he has very strong attack power very early on, and the main problem is that the longer the game lasts, the more powerful this attack power becomes, and it becomes increasingly difficult to defeat him. Therefore, you just need to get to Galtran as soon as possible and take him down (preferably in the second week). This can be done with any Castle with a well-thought-out strategy, without focusing on the economy in the first week (good players don't even build a Town Hall) and on building as many units as possible at the Castle at the expense of immediately buying monsters when building them in the first week and buying heroes to scout the territory and level up the main hero and his companions.