[Twan]

MR spells won't save regular troops, they are only usefull to protect people already having correct MR, as you can expect an endgame communion master to have full penetration gear (-5 MR) and one or two more penetration from his level if communion is large and ennemy use LoNS.

So just don't use regular troops, if you need chaff use mindless who can't be enslaved (at least if the opponent don't use arcane domination or undead mastery too).

Ideally only send thugs and mages with MR gear (MR gear = not just one amulet, you usually need 2 MR items in addition to an antimagic spell to start to be safe).If you can summon some, golems are of course a very good choice as they are immune to mind spells. As the communion master may cast soul slays or simple enslave with insane bonuses, you should expect your guys to have to resist against 9 or 10 penetration.

But you can exploit the way the spell AI use these one target spells, as your SC with the higher number of hp is the more likely to be targeted. So if you can give 30 MR to your toughest SC, he will protect a full team of thugs with lower hp and MR (it's not 100% sure but work usually).

Once you can have a thug/mages team surviving astral spells, it's rarely hard to win against astral nations (who rarely have as good access to thugs as their opponents, and usually don't have exceptionnal troops). In addition to mass dammage spells etc..., designing your thugs for making battle long + using some fatigue BE to kill the slaves can very well do the job (especially if the opponent use an half-reverse communion with some casting slaves).