an odd combination of attacks wiped out new necrons easily.

I played a very heavy black knight ravenwing list and had master of ambush.  I infiltrated a large full 10 man black knight squad with an interrogator chaplain on a bike with the mace of redemption, as well as a RW command squad with ravenwing banner (auto hit and run), behind them was another RW Command squad with a librarian with a Powerfield and the Feel No Pain banner that I scouted up to be within range of the infiltrators.
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...now, I still have 2 RW grenade launchers on the black knight squad with the chaplain that didn't jink.  The other squads did jink, so they can only snapfire.  I use the chaplain squad to re-engage his deathstar (large warrior unit with overlord and orikan) and hit him with a stasis grenade and plasma talons.  He makes all his cover + RP saves, but once i get into combat I realize something.  He was previously blinded, and blinded gives you a set WS and BS of 1, not just snap firing.  I had also hit him with a stasis grenade, which lowers his WS by 1, he is now at WS 0 for the whole squad, meaning I autohit him with all my attacks and he can't hit back.  I now easily kill half the squad and sweeping advance the rest of his deathstar.
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FOUR auto-hitting S5 rending attacks per model.
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I didn't mention in the original post but that same squad I hit with a rad grenade as well, so each of the autohitting S5 rending hits was also wounding on a +2 because of the debuffed toughness to 3!!

It also makes the rift cannon on a dark talon a bit better, as you can fairly easily line up a black knight/RW command squad to shoot and charge against what the dark talon shoots at.  You can even stasis grenade the squad the dark talon will be shooting first to increase the chance they will fail the initiative test from blind on the rift cannon.
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Page 9 is pretty clear, auto hit on WS zero, and I cant find anything that says your not stuck at 1

The rule I have on Vehicles is "Accordingly all Vehicles are treated as being Weapon Skill 1"  unless they're immobilized. p78 brb so I guess its 1, -1, again 0 

Wish I'd caught this before, its huge on vehicle assaults