Luna - the god tier hero that breaks the game. Grindan and Labetha are good because they start with Earth magic (Grindan is better in the early game because he also starts with the “Slow” spell).
Brissa is good because of her “Haste” specialty, making the “Haste” spell more effective.
Monere - good might hero, starts with Logistics and offense.
Day 1 you want to build a mage guild if you have the gold for it, because most other buildings require it. After that, it will depend on what the map gives you and what your overall strategy is. Some people like to go for the Storm Elemental upgrade. If you need to buy Earth Magic, you will usually build the Magic University on turn 2, 3, or 4. If the map gives you a few external altars of thought, you could go for building Magic Elementals. Most commonly though, after the Magic University, you will likely try to build up your Mage Guild (especially if you’re dealing with a difficult break as good spells can help you overcome something that Luna wouldn’t be able to handle with just her fire wall).
Fire wall - Luna’s specialty, her double damage allows you to do a lot with no army, using just Luna and her mana.
Armageddon - if you can find an armageddon shrine/scroll or a fire tome, you can use it with Fire Elementals or Magic Elementals.
Forgetfulness - great spell when you’re dealing with a ranged break like Cyclopes or Enchanters, in combination with Water Magic that you can buy in the Magic University it will allow you to burn ranged breaks without a problem (except for titans and liches as they are immune to mind spells).
Resurrect - great spell to have in situations where you’re dealing with a difficult break.
Summon elementals - another great spell to have when dealing with difficult fights.
Bless - Conflux units such as Air & Water Elemental have a wide range of damage, making them a perfect target for Bless
Blind - more effective than for other factions because Luna will always have expert fire magic.
Berserk - more effective than for other factions because Luna will always have expert fire magic