What am I supposed to do with Shamen?

[tinkthank]

Thanks for all of this.

A follow-up question:

I also got excited about poison slingers and undead synergizing well, but I just fail to be able to get my slingers to work. I fail miserably in every single setup I have tried.
In fact, I get the majority of them killed no matter what, unless I have vastly superior forces, in which case I win (or would win) without them.

It seems that the poison slingers also have a unoverridable urge to run out and attack enemies with their daggers -- at times, at least it seems so to me, when they must have at least 1 shot left (that is, before battle round 7). Why is this?

Where do you put them on the battlefield that they can hit enemies and not kill themselves?