I read a forum post a while back about different line of sight rules. The original Descent rule book has a nice diagram for that which we have used in RTL. However i heard in the gathered list of answered questions that the Line of sight rules from there are different. I tried looking in there and couldn't find it.

So i wanted to know are there two different sets of Line of sight rules to go by? If so is there an example to show the difference? What set of line of sight rules does everyone else go by?

A friend of mine just told me that www.descentinthedark.com has a line of sight checker on the website and recommended using that if we have any questionable targets in our future games.

Thanks

There is an informal ruling recorded in the gathered list of answered questions that says that figures that are not in LOS do not block LOS for attacks. This gives an arguably more intuitive resolution to certain specific situations where monsters are lined up behind a wall or obstacle and you otherwise couldn't see any of them. However, it's a lot more complicated than it sounds; there's at least two plausible interpretations that lead to significantly different behavior, and under any interpretation it causes a number of new problems that don't exist under the original LOS rules. My personal recommendation is to ignore it and just go by the LOS rules in the book.

There is no difference in LOS between RtL and normal Descent, except insofar as RtL has some props and abilities that don't exist in vanilla (e.g. trees, Soar).

However, you should also note that there's a minor error in the LOS diagram on page 10 of the rulebook: the corner square that is 1 space north and 3 spaces west of Silhouette is within her line of sight, and should be shaded red.

I was not aware of that online LoS tool so just checked it out. In case anyone else is wondering, it appears to use the original LoS rules.