Walkthroughs for custom maps.

Gentlemen, please share your experiences with overcoming Confluxes in custom maps. Specifically, my situation is as follows: "Unleashing the Bloodthirsty," 9th month, I wasn't in a rush, but I also wasn't stockpiling armies, so Phoenixes and Archers are causing irreparable damage to any of my stacks. I have all the spellcasters, but I don't have the Vulnerability spell, nor do I have fire magic. Also, the main enemy hero has somehow lost his Fairy, meaning the entire army is immune to Blindness/Berserk/Forgetfulness. I feel like I can pass by simply gathering troops, but this method is somewhat unappealing, and it's clearly not the method used when completing the map in 3-5 months.