My opinion remain that the defender advantage is far too big in late game, and the late game would be far more interesting with another initiative system, with a casting duration of several rounds for endgame spells, or simply without any instant offensive spell affecting the whole battlefield.
Now as Max said master enslave is nothing special, it's just one of the spells of this problematic category. Rain of stones and bone grinding (combined with fog warriors or high hp mages) are worse for me, as some nations can easily cast them 3 or 4 times in round one (if you can cast it 4 times bone grinding is the nastier spell against human nations, as it kills even the mages who had an armor to survive rains of stones). Undead mastery and arcane domination are more niche, but being lower level can be cast with better penetration bonus (and considering late game troops often include some feebleminded tartarians, undead mastery may give excellent returns for its price).
ps : red text hurts my eyes
Re: Countering Master Enslave...
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