Magic Scale

[Yvelina]

I always have my first air queen before turn 20. I hardly use air gems for anything else while there are air queens left, and I would go as far as trading hammers for air gems. I am frankly surprised that any air nation would use air gems before this... but that may explain why I have always ended with at least two air queens in every one of my Vanheim games, even when Man, Caelum and Pythium are in.

[archaeolept]

you might be under very difficult research; in which case investing in air gems might actually speed up your acquisition of the queens.

or there might be no other air nations; in which case you can be a bit lax in the rush.

[Turin]

drain 1 for ermor seems to be pretty resaonable.
your units get +1 mr, you will be behind in research anyway with ermor, but you mostly need only conjuration and construction anyway.

In one ermor game I´m in, I chose magic 3 and so far it has only hurt me. My undead are far easier to banish(-1MR compared to +1MR), my pretender could have 1 more 4point magic paths , I can´t research anyway, because it´s with very hard research settings and I must pump every death gem into wraith centurions just to stay in the game.

Taking drain2-3 though doesn´t make sense

[Agrajag]

Turin said:
but you mostly need only conjuration and construction anyway.

Unless you are playing a single-player game, and I must mention this as a single-player man.
There are plenty of great spells for Ermor all around the research table.
Utterdark, Well of Misery, Burden of Time are great globals for Ermor, also, Nether darts is pretty damn good for default Ermor.
Also, I've found its a nice idea to have some Earth magic on your Ermor (none default) pretender, it can give you good forging, a steady supply of earth gems (to convert into money, if you have to), a spell that creates a tower in one of your provinces (fortifications are hard to build as pennyless Ermor), Inulenrability for your pretender and nice globals like the mechanical militia.

[Turin]

Well,
well of misery is conjuration. The other two globals won´t work that well in multiplayer as you mentioned.
You don´t really need a lot of strategy to win vs the ai nations with ermor .

wizards tower is a waste of gems in most circumstances. you could just alchemize 45 of the 50 earth gems required and build your ermorion castle.