[Tuna-Fish]

I am not a D10 player but the reason seems rather clear: D10 gives a very nice fear for all blessed troops. When playing nation with cheap sacreds (flagellants?) mass them all together and as their effect is cumulative watch as indies, or normal armies, flee before taking a single hit. Helps initial expansion massively for some nations. Also, D10 can be very useful later in the game as many death summons give more troops for higher level caster, making your pretender essentially into a very efficient undead factory.