Mass-produced Reanimating Priests: Exploit?

[Meglobob]

Life after death is just doing what it says on the box, giving a unit wether it be militia or mage or priest a extended unnatural life.

By the time players can pull it off, the battlefield is ruled by SC's, thugs, battlefield wide damage spells and large area effect evocation and master enslave etc, etc anyway. So 50-100 per turn longdead is no big deal. If you could pull it off in the early to midgame it would be a exploit but not as a lvl 7 spell.

Doesn't it also reduce MR to 5 or something low as well? Which destroys the mages/priests usefulness on a battlefield.

I don't think its an exploit and not even unthematic as you can play a evil god with any nation.