Welcome to Librarium Online!
Our biggest problem with our casters is that they must challenge when able to.
This makes it hard for us to hide them in units, because then they will need to challenge.
I was just reading the rulebook, particularly the challenge part (I was trying to find if there was a specific order in which to place the command group and/or characters) and I came to something interesting:
Once a challenge is underway no further challenges may be issued in that combat until one character is slain or flees from combat.
Now enter the warshrine.
It gives all unit champions on the table the Eotg special rule, obligating them to challenge as well. Stick a caster in a unit of Chosen, and your caster won't be fighting anymore challenges.
This is how I see it.
Unit chosen of Nurgle with Festering/blasphemous combo. If the enemy has a hero in the unit, then they most likely will also have a champion in there to take the fall vs nasty heroes such as a chaos lord (what, wait, like the ones we have?).
If we were to simply challenge with our caster, he would accept with his killer hero = dead caster.
Now with the warshrine on the table, our champions get to challenge as well, this is where the fun starts.
The festering and Blasphemous will most likely take out the champion in the magic phase (or else we have failed our glorious lord of plagues) this leaves only his hero. We issue a challenge with our chosen champion and our caster is safe (he must accept or retire his hero to the back ranks where all the girly boys hang out)
The chosen champion rocking 3 s4/5 attacks with a 2+/4+ safe (I use halberds+shields) (with one roll on the EotG table) is capable of handling a hero level character, especially if the warshrine in is nearby and he gets a second roll on the EotG table!
Just imagine the terror in your opponents eyes.
This makes it allot more viable to put a caster in a unit without having to move and leave him out one turn before you make a charge. Only sucky part is that you won't be able to buboes sniper anymore... although, how long do you think the combat will last?
I didn't know if you already knew it or not, or even if it was worth mentioning. I thought I'd just share it with you guys.