Re: earth quake...
 

It's a bit more tricky in terms of scripting, but there is reinvigoration.

On the other hand, that requires you to set up a communion up in the first place (which means a turn for the enemy to cast earthquake).

Re: earth quake...
 

If you are spamming early earthquakes and have not yet developed fog warriors or other high-end counters, what kind of blockers do you use while your mages are casting earthquake?

Presumably anything with both high defense and high protection and preferably with regeneration so you don't accumulate too many afflictions, but is there anything else to look for?

Re: earth quake...
 

The fact is, earthquake doesn't do all THAT much damage, just 8AP. This makes it good for splatting lightly armored humans (like most mages as well as certain chaff troops like mictlan's slaves), but it doesn't really do all that much to heavily armored troops (I dropped six earthquakes in a row on MA Ulm recently and most of his blacksteel troops were just scraped up) or things with big piles of hitpoints. Just having one or two lumber constructs (from wooden construction) can draw enemy fire while surviving any feasible number of earthquakes. Giants, elephants (though be sure to give them a clear path to rout if that happens), or heavy infantry will weather earthquakes well. Also, anything ethereal will be untouched by 3 out of every 4 earthquakes, so just spam body ethereal a few times on some chaff and you're golden.

EDIT: Trolls (either normal or Sea trolls) will handle earthquakes well. And since you have earthmages capable of casting earthquake, you have earthmages capable of summoning a handful of trolls to act as a defensive line.

Re: earth quake...
 

Or just don't even bother with a defensive line. Just use it as a hit and run tactic. Earthquake with a couple of armored up mages and then retreat. Sure, you wont technically win the battle, but if you decimate the mage corps of a major army it will be worth it. For added evilness and if you have the mages, cast doom prior to the earthquakes going off. Kill a bunch and everyone left over is riddled with afflictions.

Also be sure to do your fatigue calcs correctly so you actually can retreat.

Re: earth quake...
 

Don't forget doing it as a deathblessed nation.

Re: earth quake...
 

This is just plain evil. The extra affliction chance probably isn't worth it by itself for the death bless, but as long as you sprung for the high D pretender anyway it a great use of it.