I've had this idea for some time now.
When facing horde armies, equip your sorcerer with Gift of Chaos. Target one of the little horde beasties (i face Tyranids alot).
And with a bit of luck *BLAMMO* you have a spawn in the swarm! :lol:
That should help 'ya out, if nothing else it will be worth it seeing the face of your opponent.