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So, I have had no luck finding a clear answer to this one, and really there may not be a good answer out there. However, I would like to get a feel for what people do with these two rules that seem to be in direct contradiction.
The Grotesques say they ignore hits (meaning the weapon CAN hit) that are not at least twice the toughness. It also says they are ONLY affected by shooting weapons that are Str. 6+
Str. X weapons wound on X (4+, 2+,...) regardless of toughness.
We talked about this for a long time during the game and really all came up with the same answer... the rules really just do not address this sisuation. If anyone has any ideas how to best handle this I would love to hear them.
Oh, and for that game we made it so my sniper rifles wounded on 6+ rather than 4 and my hellfire rounds wounded on 4+ rather than 2, just so we could move on with the game.
Strength X do not have a strength value thus by RaW cannot harm grotesques. [Edit] of those poisoned weapons that do have a strength value it could get really funky if any were S6 (because you don't use the weapon's strength to wound).
What you can do however is make a claim that weapons that aren't S6+ but can cause instant death can kill grotesques due to the wording of the 3rd sentence in their feel no pain entry (though I cannot think of any non CC examples).
Thanks guys... sounds good to me (well bad for me as I play SM's) but that logic makes sense.