There may be a few more thoughts regarding this type of
action:
1. For the scientifically minded, you may want to examine
the mass of the rogue and velocity the rogue achieved
by the time he met the "end of his rope" as it were. When
calculating velocity you may want to take into account
"drag" induced by the rogue...
2. Otherwise, we can use some common sense:
a.) Lets assume that the archer made his rope use and
climbing checks to create a harness that would not
immediately gut him at the end of the rope (otherwise
I would recommend the less painful falling damage;
"more area" if you take my meaning).
b.) The rogue meets the "end of his rope" (love that)
in a violent way.
c.) Unless he is using a bungee type of contraption, he
will still likely take some damage (there are walls to
consider and all sorts of physics at work here). Lets
further examine the rules:
DMGp.89 FALLING OBJECTS:
TABLE 3-18: Damage from falling objects:
200-101lb. 20ft {increment}
"...For each additional increment an object falls, it deals an
additional 1d6 points of damage."
The above rule attempts to assign damage by mass (under
200lbs) and distance fallen. The only other rule that may
further apply is "falling into water" to simulate some sort
of "cushion".
DMGp.112 OBSTACLES, HAZARDS AND TRAPS:
"Falling into Water: Falls into water are handled somewhat differently. ......the first 20 feet of falling do no damage. The next 20 feet do subdual damage (1d3 per 10ft increment). Beyond that, falling damage is normal (1d6 per 10-foot increment).
Characters who deliberately dive into water take no damage on a successful swim or tumble check (DC 15), so long as the water is at least 10 feet deep for every 30 feet fallen. However, the DC of the check increases by 5 for every 50 feet of the dive."
Given these clarifications I would rule that:
I. Meeting the "end of your rope" even with a nice harness
is ever so much more violent than diving into water. The
harness would require a use rope check (DC: 15) and
climb check (DC: 15). Do not forget the end tied to the
battlements (DC: 10 or 15 if tied one handed)
II. Damage might be 1d6 per 20ft fallen, rounding up (3d6
for a 50ft drop). The first 20ft is subdual.
III. A successful tumble check (DC15 for 20ft increasing by
five for every 20ft fallen; again round up (DC25 for 50ft)
will reduce damage by half.
IV. A successful concentration check will allow an action
at the end of this time (DC10 + 1/point of damage).
V. If the rogue has an item in his hands when he meets
the end of the rope, he may drop the item. I recommend
a reflex save (DC: 10 + 1/pnt of damage sustained).
VI. As far as movement is concerned, I am unaware if
falling counts against your "max move" during a round
(though, interestingly, a "dive" attack is treated as a
charge with a minimum of 30ft moved). Again, given the
violent nature of the halted movement, I believe the
point is moot (not many people rule in favor of the
"jump off a cliff, bounce, and move/run" scenario during a
single round.
....Of course I may be wrong; Your DM has enough on his
plate without rolling 10+ dice to adjucate one (un?)heroic
action. I just don't meet many rogues willing to try stunts
heard in a local bard's rendition of "Die Hard". They usually
just drop their weapons and say something like "Ya wanna
get rich??"
~D
