Hidden Cities - 1
This is the third Sky Island, home of the Goddess Fellana. Gares, the Dark Prince, has occupied it, however, and you get to free it. Joy. Be aware that the stage is harder than Antalia, though not by much.
Send a unit along each of the three branches leading from your base. One should go straight north to Shellmat and stay there. One should head east and liberate everything along that road (2 cities), stopping at the end (Nushatl), just southeast of the enemy base. From your vantage point there you will be subjected to attacks by flying units, but with some strong spellcasters that's not a problem.
Your third unit should head along the western road and north, across the river and straight through the mountains to Rusheln. From there, wait until the next wave of enemies ends and dash across the bridge into Interake, just southwest of the enemy base. Now fly around the map, liberating whatever's left over, and wait until the enemy runs out of money. Be advised, you'll need a healer in whichever unit you used to take the western road, as that is the path that Undead will take.
If you have any spare Charm items, use them in this stage as the enemy comes with Tiamat dragons. Those dragons on your side for free - what a cheap trick, no?
Anyways, once the enemy flow ends, liberate the hidden Temple on the island in the center and assault Shangrila.
You may remember him from Island Avalon, where he was absurdly hard. Well, meet him again, where he's much easier! He comes with two Salamands, one of which can and will cast Nova (a very, very strong area-attack Fire spell) but you should dispose of him before they do so.
Basically, use Seraphim. There's one in my unit as illustrated here (Yushis). Her attack (Jihad) will do, oh, around 100 points of damage. With that sort of firepower, you can just wait until she casts Jihad, Retreat, and attack again so she can re-cast it. A Judgment card will do around that much damage to Gares as well. He gets one very strong Black area-attack spell, Evil Dead, but it won't kill you, although EvilDead followed by two Novas from the Salamand in the back very well might.