REACTIVE DETECTION RANGE
If you look at the Spot and Listen skill descriptions you will see a statement to this effect, "Every time you have a chance to spot something in a reactive manner you can make a Spot or Listen check without using an action." That is basically saying what we all know to be logical and true--that a character should have a chance to see or hear an enemy as long as he's conscious.
But, how far can he see? How far can he hear?
The answer to those two questions comes in a number that I am calling the character's Reactive Detection Range. If an enemy moves or makes noise within the character's RDR, then the character has a chance to detect his enemy.
CALCULATING THE RDR
The character's Spot RDR is equal to the total of Taking 10 on his Spot check in tens of feet. For example, Silaigne has +4 on his Spot checks with an additonal +2 bonus when in his native evnironment. Thus, Silaigne is Spot +4 in dungeons and under ground and Spot +6 in his native wilderness.
This means Silaigne's RDR is 140' underground and 160' above ground in the wilderness.
The RDR is something that a GM or player can figure in a millisecond, on the fly. If you know a creature has Spot +8, then you know his RDR is 180'. If you know a character has Spot +2, then you know his RDR is 120'.
MODIFYING THE RDR
If the character is distracted, then his RDR suffers as his focus is shifted. The game applies a -5 modifier to distracted characters. Thus, when figuring the RDR, apply the modifier on the skill before multiplying by 10 feet.
If a distracted character has Spot +8, he is an effective Spot +3. Thus, his RDR is 130'.
The GM may impose other appropriate modifiers. For example, out on a flat, desert plain, at noon on a cloudless day, where a character can see for an incredible distance, the GM will place a theoretical positive modifier on the RDR so that it has great range, making it impossible not to see an enemy's approach.
In a dense jungle at dusk, visibility may be limited, thus the GM may place a penalty on the character's Spot check, which, like the distraction above, will reduce the character's RDR.
RDR can also be reduced due to lighting or other visibility conditions.
THE RDR IS LESS POWERFUL AT RANGE
Think of a character's RDR as an area surrounding the character where the character is constantly making Spot checks. Because he is considered to be constantly making checks, we use the average by Taking 10. Because Spot checks are penalized at a -1 modifer per 10 feet, the RDR becomes less effective the closer you get to RDR range limit. Thus, a character's RDR is more effective at 30' than it is at 100'.
Another way to think of this is to consider the character surrounded by a number of 10' wide bands, circling and centered on the character. From the character out to 10', the character is considered to benefit from his full Spot Take 10 total. At a distance of 10-20' from the character, the check is the character's full Spot Take 10 total minus one. And, so on.
A character with an RDR of 150' has a series of the concentric check zones that looks like this:
Code:
Distance Spot Check
0-10' 15
11'-20' 14
21'-30' 13
31'-40' 12
41'-50' 11
51'-60' 10
61'-70' 09
71'-80' 08
81'-90' 07
91'-100' 06
101'-110' 05
111'-120' 04
121'-130' 03
131'-140' 02
141'-150' 01
THE ENCOUNTER DISTANCE RULE
As described in the Spot skill description, the distance at which an encounter starts can be determined by making the enemy's Hide check, subtracting that roll from the character's Take 10 Spot number, then converting to 10' units.
Out in the wilderness, Silaigne is Spot +6, and Taking 10 give the character a total Spot of 16. To find out how close the panther got to the party before it was spotted, simply roll the panther's Hide check and subtract that total from Silaigne's Spot and multiply by 10 to find the range. If the panther rolled a total of 11, then Silaigne spots the panther at 16 - 11 = 5, which means the encounter begins with the panther spotted 50 feet away from Silaigne.
What if the enemy has a higher check? Should the enemy's Hide total be higher than the character's Take 10 Spot check, then the enemy is able to ambush the character during a Surprise Round.
Let's say the panther rolls 22 on his Hide to Silaigne's Take 10 Spot of 16. The means that the panther successfully sneaks up on Silaigne and can ambush him in a Surprise round.
How long does it take the enemy to reach the character? This question is for the GM to answer, but remember the character's RDR. Silaigne's RDR is 160'. The stalking panther's Speed is 40', but while stalking, it will move no faster than half speed to avoid taking the penalty to its Hide and Move Silently checks. It's not always important to know, but when it is, we can assume the panther moves at Speed 20' each round and needs to cross a minium 160'. This means it will take 8 combat rounds, or about 48 seconds, for the stalking panther to reach its target.
ACTIVE SPOTTING
According to the Spot skill description, a character can attempt to spot an enemy in a reactive manner any time the character has a chance to spot them. This is covered under the RDR above. If a player calls for his character to perform a spot check, then active use of the Spot skill is a Move Action.
MULTIPLE SPOTTERS
Rarely in a roleplaying game are the player characters alone. If the party is composed of four characters, it can be quite a chore for the GM to figure four Take 10 Spot sums vs the enemy's single Hide throw. It is easiest and logical to simply take the Take 10 sum for the character with the highest skill bonus. At times, though, a character with a lower Take 10 sum may be more appropriate (due to the character's location, for example).
So, when rolling Hide or Move Silently, the GM should simply make one Hide or Move Siliently throw and compare it to the most appriate character's Spot or Listen Take 10 sum. In effect, the character's Take 10 sum is a DC for the enemy's Hide or Move Silent check.
At the GM's option, a single d20 throw can be made for reactive Spotters and Listeners. This is an extra step for the GM, but it does throw variety into the mix. Simply make a single die throw and add the highest Spot or Listen bonus from among the party members.
SPOT OR LISTEN
Just about all that has been reported above about the Spot skill can be applied to the Listen skill. A GM can roll for both Spot and Listen, if he wants to, but it is easiest picking the character's strong suit and simply playing to that strength.
There can be a Listen Reactive Destection Range just as there is a Spot Reaction Destructon Range.
Instead of figuring multiple RDRs, simply figure the RDR for the most appropriate character, or the character with the highest skill. The most appropriate is not necessarily the same, as a character's positioning may come into play.
Instead of Taking 10 to determine a character's RDR, the GM can roll it normally for varied results.
EXAMPLE OF PLAY
Silaigne and Caelis are traveling across the Cracked Lands where the terrain is such that the two can only cross one mile per hour. The normal day of walking is 8 hours. Outside of that, the characters risk fatigue and exhuastion.
The GM rolls for a daily random encounter and finds that the party will encounter a panther this day.
Throwing 1d8, the GM randomly determines that the panther will be encountered around 11:00 am. It's an overcast but shadowless day.
The GM has pre-recorded each PC's Spot and Listen checks. With Spot, Silaigne sits at Spot +6 and Listen +2 while poor old Caelis has Spot +0 and Listen +0.
Of the two, the GM uses the character with the best chance of catching the panther, which will be Silaigne and his Spot skill. The GM determines that Silaigne is not distracted and no modifiers are required due to terrain or visual conditions. Therefore, Silaigne's Spot RDR is 160'.
Secretly, the GM rolls for the panther's Hide and totals an 11. This means that Silaigne will spot the panther before it attacks, and he will spot it at a distance of 50 feet.
Therefore the GM describes the two PCs as they cross The Cracked Lands, rounding a bend only to see the crouch on a ledge 50 feet ahead of the PCs. Roll initiative. Go into combat rounds.
SECOND EXAMPLE OF PLAY
The GM rolls for random encounters once per night and once per day. The panther from the day's encounter ran off after its first hit to lick its wounds. The GM rolls a second encounter that night, and again it is a panther. So, the GM surmises that the same panther is hungry and has stalked the PCs throughout the day.
The moon has replaced the sun, and it is so dark out in the Cracked Lands that neither Silaigne or Caelis can see their hands in front of their faces if it were not for the fire they had built, assembled out of the scarce wood from the area.
Visability is extremely limited in this situation. The fire illuminates 40' brightly and another 40' in shadow. This makes Silaigne's (and Caelis') Spot RDR at a maxium 80'.
Silaigne's Listen skill, though, is +2. Thus this stealth battle will be between Silaigne's Listen and the cat's Move Silently skill.
Therefore, Silaigne's RDR score is 12 with a range of 120'. The GM secretly rolls the cat's Move Silently and gets a total of 8.
The GM describes how, over the crack of the fire, Silaigne hears something out in the darkness.
12 - 8 = 4. The Panther is in the shadowy area of the fire, just at 40' from the characters. This puts the panther in the character's limited Spot RDR range. Secretly, the GM throws the panther's Hide against the PCs' RDR number.
Using Silaigne again, the cat throws an 18 Hide, which means neither Silaigne (Spot 16) or Caelis (Spot 10) see it (Spot 16) out in the dimness of the fire.
"You definitely hear something, but when you turn, you don't see anything," The GM says.
Both players want their PCs to look around to see if they can see anything, making active Spot checks. Since the reactive Spot failed, the skill reads that active Spot checks (this one with a maximum distance of 80' due to the fire and the night) require a move action.
Both checks fail. The panther, though, can see both characters clearly due to their proximity to the fire (not to mention low-light vision without the fire).
The GM decides to have the panther pounce of Caelis (a pounce is a combination charge and full attack), so he describes this lightning fast black beast that blasts in from out of the darkness, straight at Caelis. Initiative is thrown, and the combat is played out normally.
