I also reached the Titans. But I need to replay everything from the beginning. To defeat them, you need to play almost all the previous battles with very little magic. The point of the battle with them is that you need to place 1 fly in front of them, and 2 near our archers; then the Titans will run straight to our archers, and in the narrow isthmus, you can surround them with units from both sides. Of course, the units are not infinite, but with poisoning from a wyvern, blessing on the lizards, and restoring our killed stacks + a couple of morale boosts, you can win the battle. But for this, you need to have a mana reserve, which I spent in the previous battles. I've roughly figured out how to pass the battle, but I've put the map aside for now.
Something like in the screenshot, but with 0 magic. Also, as I think, the attack should be given to Dessa, and the defense to Ciel. Because Dessa can deal additional damage with a ballista with an attack of 46 or 48 in the battle with the Titans. In general, I'm on pause. I found a more interesting map.
And what are you playing? I'm currently playing The Legend of Fairy Sword IV, which is also interesting.
I just looked, and it also needs to be replayed; at least, the battle with Alamalor should be played with Ciel; I just saw that she has Eagle Eye, so that's where the resurrection comes from)