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It says they count as in cover for assaults...does that mean they get their cover save of 5+ even against power weapons? And in a crater would this be 2+? or is this rule ONLY there to say they strike first? Although they go to some effort of saying them seperately...
Are fearless units immune to terrifying? Or not.
As it is worded as "Always fall back and do not take leadership"
and fearless is "Automatically passes leadership tests" if i'm not mistaken...
You may never claim a cover save in close combat, it is for use against shooting attacks only. Instead, the Mandrakes count in cover for the sake of striking first, as you said; though keep in mind that grenades will still effect them, as if in normal cover.
Thats also what i thought, but i read a player doing it differently and thought id ask. That makes "sense" but the wording does make in fairly amiguous.
Grotesques Vs. Fearless is a debate which comes up occasionally
Grotesques stop the leadership test, so that's not the issue but rather Grots say
"Any opponent beaten by them in close combat automatically falls back"
and Fearless says
"Fearless troops [...] will never fall back"
It's a classic unstoppable force vs immovable object argument, In this instance as much as I would love the grots to force fearless units to fall back, I tend to let the Fearless units stand their ground, because a) it's not some will bending power but simply the grots are meant to be scary, which is exactly the sort of thing fearless units aren't meant to be affected by and b) I think "never" carries more weight than "automatically" for example, if a unit had to "automatically fire at the nearest target" I wouldn't consider that wording strong enough to let the unit fire heavy weapons after moving.