A THREAD FOR NEWCOMERS!

3. There is no army because I attacked his main castle.
4. There is a Dimension Door, Expert Logistics, Chain Lightning 285 damage, 40 000 money, and a bunch of resources
The map is large without water, about 70 percent not yet captured)

Stall for time! Fly around the treasures, collect wyverns from the hives, don't worry too much about the castle; you can buy any growth on the first day (Dimension Door), including in his castles. Be sure to spend the money on something useful. You can build up the Mage Guild in the left castle and gather spells.
And most importantly—get some artifacts; Chain Lightning at 285 against Arch-Devils is way too weak, that's more like Fireball damage, and stats 3 8 8 6 are also low. You can find troops in Pandoras. Once you build up strength, gut the Dragon Utopia. Then head to the finale so he doesn't get too powerful.