After digging through some old stuff of mine and discovering that I actually did still have Master of Magic (though I do still aim to get the GOG version as well in case something might happen to the other) I recently installed it and started playing again, having a pretty good time with the straightforward light magic and warlord combo, and I'm already starting to consider my options for further playthroughs... However, my understanding of the way the magic and spellbooks in the game actually work has sort of... Vanished.

So I thought I might ask here, what combination(s) of spellbooks and abilities let you get the most out of node mastery? Or is it even really worth it? Are there better choices for becoming more of a magical power-house rather than relying as much on heroes/champions and basic units with adamantine weapons and ultra-elite+ status?

First off, node mastery requires that you have at least one spellbook each of chaos, nature, and sorcery. While it may be tempting to take an even split between the three, I'd recommend taking only 1 book of two of them, then as many as possible of the third. I'd recommend against taking any additional retorts besides node mastery, as you'll already be stretching your spellbooks pretty thin. For gameplay, the big advantage of node mastery is that you'll be able to capture nodes sooner (since you'll be able to provide much more spell support during the assault) and once you take the nodes you'll have twice as much power coming in from them, so any playstyle will want to take advantage of this additional power.

The particular playstyle will depend on what type of spellbook you ended up maxing. Nature has lots of good unit enchantments, so with that a bit part of your approach would be buffing up your units, making use of that extra mana that's coming in to support the additional enchantments. Sorcery has some powerful high level summons (such as Sky Drake) which you'll want to take advantage of, along with using the counter-magic spells to keep your opponents from doing too much with spells. Chaos has some nice early summons (hell hounds are great offensively) along with some strong late-game summons (such as Great Drakes), and really shines when it comes to combat spells, so be sure you've allocated some of that extra power coming in to spell skill so that you can fire off additional spells during combat. Chaos also has some high-level global enchantments that are very nasty, causing all sorts of problems in enemy lands and cities.

As for a magic-heavy style as opposed to a more standard military style, summons are the main option there. If you're able to have enough mana coming in to support an army of summons they can be extremely powerful, with the high-level ones being able to give even the strongest heroes a tough fight. Death is actually one of the best spell types for this approach, as it has some very good summons at all levels (cheap skeletons and ghouls at lower levels, then shadow demons, wraiths, death knights, and demon lords as you get more powerful spells).

Okay, thanks for the info. I wager I'll probably go for nature spellbooks next game I start, since I found the wikia for this game and the Great Wyrm sounds to my liking.

And as for death, would it not be better to go for Infernal Power instead of Node Mastery?

I'm a relative newcomer to Master of Magic, but in the few games I've played I found that Nature has a lot of good summons. I was able to wipe out some enemy wizards with just a few basilisks (although I was playing on easy) and sprites are really good in the early game because they can fly and shoot enemies from afar, and the enemies often can't counterattack. If you have enough sprites to take out the enemies without running out of ammo for their magical ranged attack, you can win without any casualties. I hardly used any normal troops at all.

And Great Wyrms are indeed awesome.

Yeah, I wasn't talking about death in the context of a node mastery approach; sorry if I didn't make that clear. Death is actually a poor choice for node mastery (along with life), since you have to spread your spell book choices even thinner in both of those cases.

Just played a fun game using Alchemy, Archmage, Node Mastery, LLLLCCNS.

I'm squeezing every enjoyable moment out of easy difficulty. For fun, I'm using:
* node mastery
* alchemy
* artificer
* runemaster

While I'm more focused on making items for heroes, one of the benefits is hero spells at nodes. Spellcasting heroes don't fizzle during combat at nodes. That node mastery benefit allows me to win battles with summoned creatures. Also helps my hero healer cast her spell at nodes.

Node mastery further multiplies my mana, which I'm using to feed my hero + item factory. Add to heroes spell skill with items, then build more powerful items in the same number of turns. Finally turn them loose capturing nodes.

Practically speaking, spreading my spell book picks over nature, chaos and sorcery has been successful. The lower spells are most useful to me.