--Magic Use--
I have 1 word for you, 1 word to describe the crux of your superiority in late game, over all other elements - Death Gems. No wait, that's 2 words..... oh I've got it - Morrigans. That's what the Death Gems are for. In time, you will want to churn out several Skull Staves, and you will give these to A1/D1 Druids, and set them to (M)onthly cast Summon Morrigan. Beyond that, you need Dance of the Morrigans. It is seriously, undoubtedly, the most powerful Battlefield Enchant in the entire game. The way it operates, is similar to Mists of Deception, in that you get Morrigan spawns at the edges of the battlefield, and they continuously spawn throughout the combat. Well, that's neat, right? Well yes, except Morrigans are like Valkyries on PCP. And they come with Life Draining weapons. Oh,
and they can fly in Storms.
Let me explain how you can devastate army after army in the late game, with little likelihood of defeat except by the most contrived of circumstances - For this, you probably want 4 Kings, 2 of them need a Bag of Winds, and a Winged Helmet - the other 2 need Skull Staves and Skull Helms, and don't leave home without your Staff of Storms. Also, if one of your Air casters can carry one of the Holy boosting artifacts, all the better, or bring your Prophet along, as this army is both Hammer and Anvil as one. Another nice trick to throw in, if you can gain access to Crystal/Slave Matrices, is to bring along 4 Druids with Slave Matrices, and your Kings with Crystals, but this is doable without either (and without Divine Bless, it is just the au jous for your sandwich). Your combat will look much like this - Turn 1 - everyone casts Summon Storm Power, except for your 5D casters, who cast Dance of the Morrigans, and Darkness (oh did I forget to mention, since they're Undead, they also have 100% DV). Second round of combat, you cast Fog Warriors, Wrathful Skies, and Storm Warriors. By the time you are in the third round of combat, you really don't have to do anything - though now casting your Divine Bless will leave you with an awful lot of Quickened Morrigans. If you brought some extra Morrigans with you (it's a good idea), say 30-40 of them, have them set to Hold and Attack Closest. Let your Kings rain down whatever they want, it literally doesn't matter at this point. By the end of combat, the last few enemies will be literally engulfed in a sea of Glamoured, Quickened, Life Draining, super high Defense Morrigans. Your opponent will probably set to AI.
Now, aside from this, I promised to talk about your Unmarked Champions a bit. Here's the thing, in the early game, especially with a handful of Unmarked set to Guard Commander, to bulk up numbers a bit, squads of these guys can tear up almost anything. Adding in a few Druids to throw down Phantasmal Warriors (Phantasm = size 2, Unmarked = size 4, you do the math), and some supporting Lightning, make these very effective auxilliary forces. Also, as mentioned, throwing in 10-20 Firbolgs will also dramatically enhance staying power in many circumstances. As your research and gem income increase, you will want to look towards giving these guys a Frost Brand, and a Pendant of Luck. If you managed to secure a source of Hammers, that is 6 gems for a very potent thug. Due to potential Fatigue issues, they are not meant for solo use, but they are so cheap to purchase, maintain, and gear, that squads of 6-10 of these become trivial to deploy into multiple weak points, defensively or offensively. Eventually you can mix and match other low cost items to tailor them to specific enemies - 4 of these guys with Dusk Daggers make quick work of any less mobile thugs the enemy employs, to free up Kings for the more high tech challenges. Also with enough Unmarked Champions at your disposal, you can very effectively use them to discourage enemy raiding forces - your PD may suck, but who knows where your thug patrols will be this turn?
Remember those Nemedian Champions? I bet you know what they do, now. 1xFlying Shoes + 10 or more Morrigans + 1 Nemedian Champion = very potent, highly mobile, fully Glamoured raiding force. The Champions can even Bless the Morrigans in combat, it's like a dream come true.
Just remember, with Fomoria, Speed = Brutality. Lightning is great and all, but you can resist Lightning, you cannot resist the Blitzkrieg.