Guys, this has been a subject that I have been pondering on for a while now. I was thinking is you get six to wound on knights with lances, and they're in the firelance starhost, does the amount of mortal wounds get doubled to four from the base one, the additional one for the starhost and then doubled by the starpriests celestial venom. Or does the first single mortal wound get doubled to two and then one is addend from the starhost to three mortals. Either way this is a very powerful thing and can be very useful for line-breaking!
I believe the two things happen separately so it would be 3 wounds, but you are correct, it's a fantastic line break!
Sadly, it doesn't work. Blazing Lances: If the wound roll for a Celestite Lance is 6 or higher, the attack inflicts an additional mortal wound Serpent Staff: ...whenever models from that unit attack with their bite or jaws, a wound roll of 6 or more causes twice the normal amount of Damage .
Basically, if they charged in the same turn, and also have the Serpent Staff buff, then every wound roll of 6 does something special!
Still, Saurus Cavalry-Skink Starpriest is one of the better Vicious Jaws-Serpent Staff tandems, if not THE best -- strategy-permitting, of course. http://www.lustria-online.com/threads/ixts-unit-formations.16584/page-3#post-154335 You're on the right track! =]
Slightly OT, but, now that I think on it, I realized another nasty combo. As said, when you buff a unit with serpent staff, whenever models from that unit attack with their bite or jaws, a wound roll of 6 or more causes twice the normal amount of damage. When Kroxigor jaws roll a 6 to wound, the damage is not "1", but it's a contest between a d6 from the kroxi and the target, and if the kroxi wins, the difference is the damage it deals. With SS, you could potentially deliver 10 wounds!
I prefer the bonus from the bloodclaw starhost. Every bite or jaws attacks increase by one. Then you use the command ability of the scar vet on cold one on the knights. With this they made 4 cold one's bite attack. With the SP buff on sic to hit the do double the damage. With tis combo you have a unit (minimum 5 models on it) that starts with 4 attacks per model that will do double damage with the 6 on the hit roll. If you field a sunblood they can repeat hit rolls of 1
I fear there's a little confusion, here. AFAIR, The BloodClaw starhost gives an additional attack only with the "powerful jaws and shield" with the ScarVet you'll have, for each knight: 1 attack with the lance 2 Attacks with powerful jaws 3 Attacks with CO's bites The Sunblood, then, let you repeat all failed To Hit. The Serpent's Staff doesn't let you do double damage on 6 on to hit, but on to wound
Don't worry. The idea is nice... We’re talking about 5 attacks for each model that can benefit from the Staff. 5 models deliver 25 bite attacks, rerolling failed to hit; you probably will end rolling three or four 6s " to wound "