Our army list has pretty pricey lords so below 3000 points it tends to be either a Slann or an Old Blood on a Carnosaur (I'm discluding the Old Blood on foot because I think you don't gain enough over a scarvet to justify the points) At the 3000 point it opens up a bit. What have been people experience using: A) Dual Slann - For 750 points they can both be reasonably outfitted, One in TG one etheral running solo B) Slann + Carn on Oldblood - If you keep the Old blood cheap (Armour of Destiny, GW, Frog Poison) you can afford to have a Slann with one disciple, bsb and 25pts of magic items. C) Don't spend 750 in lords and just rock one Slann as per normal.
I've got a 3000 point battle coming up against skaven, I have gone for slann with 2 dicaplines, and cupped hands! And the old blood on carno!! With bane head!! 748 points
Was g give bsb to slann but do have a scar vet with horned one running around with some coldones so will give it to him!!
I would rather take the slann as the bsb everytime vs a scar-vet. Sure, the scar-vet is very good at the BSB role, but the slann is the best BSB in the game. To my knowledge, the only one that can take a full compliment of magic items along with a magic banner. In a 3k game, I would lean toward a double slann list. The times that I have taken an old blood on Carnosaur, I just was not impressed. One of those times, the old blood (and Carnosaur) were killed by a HE dragon prince (or lord).
My biggest fear is the carno getting cannon'd and 400pts poofing first round. Big downside with the dual slann is you need to get some decent winds or it'll be a waste. But I love the idea of have a Life and Death or Light and Shadow pairing.
At some point I want to try a Slann and an Oldblood with Wizarding hat. You don't really need 3000 points to do that though. Oldbloods don't have to come on Canrosaurs, though unless you plan to spend lots of magic items, you are better with a Scar Vet.