First of all, I would like to thank the good people at FFG for creating such a wonderful game. I must say that this was an excellent way to bring the feel of Space Marines to an RPG setting and which captures the feel and epic power of the Astartes according to the books in the black library. The artwork is elegant and the story is great. Good job and keep up the good work.
One thing that struck me was how utterly powerful Space Marines could be under the right circumstances, and how it was possible in the game to see how a small group of Marines could turn the tide of a war.
Seeing the expaned rules for hordes, I could appreciate the way that they could simulate a conflict against a great mass of enemies. 30 horde points being a mob, 60 being a "thronged phalanx", 90 being an assault force, and 120 points being a "serrated horde". Now I had to think about the last one for a second, a "serrated horde" conjures up an image of a swarm so large that you see waves in it similar to sand dunes in the wind. I could only think that that would be for tyrranid (or maybe ork) enemies as the Tau probably don't have the numbers (and probably top out at assault force).
Now, seeing that there are squad endevours that would help defend a Space Marine squad such as "Dig In" which allow a squad to buckle down behind sandbags and better protect them against shots from the horde (I reckon that a sandbag would have armor of 8, doubled to 16 due to DIG IN, which is added to the already considerable armor and toughness of the Space Marine on the protected areas).
In terms of Damage, the Space Marines cannot miss a horde of that size and probably would score about 4 to 5 hits EACH with their bolters going full automatic. Each one would cause a hit since I cannot see how the power of a bolter can possibly fail to damage a hormagaunt or fire warrior. With a squad of 6 marines, I reckon that would be 30 to 33 hits a round against the horde assuming one of them has a heavy bolter.
That would mean it would only take a few turns to demolish even an assault force or a "serrated horde". Being in cover, they might suffer a few hits but the cover could even negate that damage. I could not help but notice that even with horde bonuses, Space marines can still survive many hits.
So a half dozen Marines can destroy an assault force in a number of turns and only suffer a few wounds, but the loss to the Tau for having lost an "assault force" would be devistating to their war effort. How is that for a game changer.