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I searched around for the ruling on this, but haven't been able to find anything specific in the forums or in the rulebooks. Can a Dire Avenger squad Bladestorm during the Shooting Phase, then proceed to Assault in the same turn?
Bladestorm allows you to fire in the shooting phase with an extra shot.
Does the description of Bladestorm mention changing any of the characteristics of the weapon other than its rate of fire?
Since the power does not alter any of the other characteristics of the weapon in question, it retains its core ability (Heavy, Assault or Rapid Fire as appropriate). And we should all know what category the avenger catapult falls under, right?
* "I'm Significant!" -screamed the dust speck
* "Call me old fashioned, but an evil ascension to power just isn't the same without someone chanting faux Latin in the background."
As Forsaken said - it doesn't change the stats of the weapon in any way other than allowing you to fire an extra shot. So, for a direct answer - yes you can.
Excellent - thank you. I think perhaps I was thinking too hard about the situation. I definitely didn't see any rules that would prevent them from doing so and should have followed that. Again - thanks!