OK, I will ask the inevitable FAQ question. Which way should a unit retreat when hit by an archer that is directly above the hit unit, meaning the line of sight is straight along the border of the interveneing hex. Who choses whether the unit retreats left or right?

You can see an example in the reference book.

If the archer would be directly above the hit unit, the retreat wouldnt be left or right, would be just in the opposite direction

I probably did not describe the issue very well in words. I am referring to the case where the range is 2, and the line of sight is traced directly down the intervening hex border.

If one extends the example for tracing LOS sight that the attacked can nudge that line left or right, then that would suggest that the attacker can choose whether the defender would need to retreat back left or back right?

What was the exchange rate between pictures and words again? =P

Note: I'm using the cheapest of the cheap image hosting services, so hopefully the link will stay active long enough to help the OP get his answer. =)

I imagine the choice would go to the defender. A unit should never be forced to choose a retreat path which would damage it if another path is available (and legal). But, I'm not the designer. The way retreats and support work in this game seem to have changed the spirit of the retreat result into more of a delay tactic and less of a lethal one. Given that, I'd let the defender choose until we get a ruling.

It is covered in the reference book. It's actually the attacker that must choose which way to "shift" the line of sight. Of course, if shifting in one direction would block the line of sight, then it must go the other way. But if both sides of the line are clear, then it's attackers choice.

Edit: Page 6 "Line of Sight":

sounds like the correct answer!

I guess that does make sense. Kinda arbitrary, but it makes sense now.

Edit. The example given on page 6 in the reference guide is for LOS. The shift is given to allow a shot through what otherwise would be blocking terrain. This doesn't have anything at all to do with retreats.

FWIW the idea that it's attacker's choice is consistent with FFG game design in general. They have a tendency to favour the attacker in cases like this, to discourage turtling on the defense and drawing out what are typically already pretty long games.

I interpret the rules that an attack needs to go through a hex side. As an attacker with straight LOS on a Hex corner, since I am allowed to shift my LOS if possible, I can determine the hex side I will attack through, hence determine the permissable retreat route. If there is an obstacle on either side, I would have to conduct the attack through the opposite hex side. While this is not spelled out explicitly in the rules, I think it can be inferred from the raneg attacke rules and the LOS rules.